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ULTIsfiell, the integrated user interface, makes sure allyour design information is transferred correctly fromULTIcap to ULTlboard. Good manual placement tools arvital to the progress of your design. therefore ULTlboardgives you a powerful suite of REAL-TIME functions suchas, FORCE VECTORS. RATS NEST RECONNECT andDENSITY HISTOGRAMS. Pin and gate swappin allows,you to further optimise your layout.

Now you can quickly route your critical tracks.ULTiboard's REAL-TIME DESIGN RULE CHECKwill not allow you to make illegal connections oviolate your design rules. ULTlboard's powerfulTRACE SHOVE, and REROUTE -WHILE -MOVEalgorithms guarantee that any manual trackediting is flawless. Blind and buried vias andsurface mount designs are fully supported.

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simply by drawing the outline. The polygonis then filled with copper of the desired net,all correct pins are connected to thepolygon with thermal relief connectionsand user defined gaps are respectedaround all other pads and tracks.

ULTlboard's autorouter allows you tocontrol which parts of your board areautorouted, either selected nets, or acomponent, or a window of the board, orthe whole board. ULTlboard's intelligentrouter uses copper sharing techniques tminimise route lengths. Automatic viaminimisation reduces the number of vias todecrease production costs. The autorouterwill handle up to 32 layers, as well assingle sided routing.

ULTlboard's backannotation automaticallyupdates your ULTIcap schematic with any pinand gate swaps or component renumbering.Finally, your design is post processed to generatepen / photo plots, dot matrix/laser or postscriprints and custom drill files.

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ISSN

April 1995Volume 21Number 232

0268/4519

ELEKTUR CONTENTSELECTRUNIN

In next month's issue I s

FOCUS ON: 54 New amplifiers simplify wideband techniques AR * 8 'b.

1as

AUDIO STANDARDS& TEST METHODS

A Maxim Integrated Products Application i. Alc, :

MIDI analyser I' : I I e ii ' -Digital sine wave 9 'generator 20 FOCUS ON: Microcontroller development systems

NiCd battery -quality testerBy our editorial staff

Rechargeable alkaline Function generator - p. 8batteries

. .I

89C5 1 programmer 14 CHIP CARDS: an introductionADR-Astra digital radio Based on an article by J. Heineand others for yourcontinued interest.

30 COURSE: The digital solutionPart 5: Storing dataBy Owen Bishop

36 PROJECT: Stepper motor controlDesign by B. Yahya

48 PROJECT: Electronic barometerDesign by J. Ruiters

62 PROJECT: Bat detectorDesign by L. Lemmens

76 PROJECT: Sun blind controlDesign by A. Gessler

Front cover Chip cards - p. 14Many computer owners use

Itheir computer to controlelectromechanical systems. 8 PROJECT: Function generator ..In such applications, it is Design by H. Bonekamp .

often required to switch andcontrol stepper motors. The 1 0 1 . Z ' 9 \'circuit presented on page 36 -. -communicates with the PCvia the serial interface, and is

818280

Book availability & pricesBuyers' guideCorrections to earlier articles

.'..r. r....capable of driving two 5 From the World of Electronics Focus on microcontroller systemsstepper motors. One of these 82 Index of advertisers p. 20takes whole or half steps, the 70 Readers' servicesother half steps only. The 7 RS Components International goes CD-ROM, toocontrol board is a 81 Switchboardgeneral-purpose design thatis suitable for a wide rangeof applications involving

72 Terms of Business

stepper motors. i

Copyright © 1995 Elektuur

A B CAUDIT BUREAU OF CIRCULATIONS

Bat detector - p. 62CONSUMER PRESS

Elektor Electronics is published monthly, except in August, by Elektor Electronics (Publishing), P.O. Box 1414, Dorchester, Dorset DT2 8YH, England. The magazine isavailable from newsagents, bookshops, and electronics retail outlets, or on subscription at an annual (1994/95) post paid price of £28.00 in the United Kingdom; airspeeded:

£35.00 in Europe, £44.00 in Africa, the Middle East and South America; £4600 in Australia, New Zealand and the Far East; and $US 59.00 in the USA and Canada. Second

Class Postage paid at Rahway N.J. Postmaster: please send address corrections to Elektor Electronics, c/o Mercury Airfreight International Inc., 2323 Randolph Avenue,

Avenel, New Jersey, N.J. 07001.

ELEKTOR ELECTRONICS APRIL 1995

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ELEKTOR ELECTRONICS APRIL 1995

From the World of ElectronicsConsultative expertise - by

satelliteThe development of the CAMNET telepres-ence system by British Telecom Labora-tories (BTL) is about to revolutionize manyof our ideas and practices concerning re-medial aid at a distance. The term reme-dial aid is used in its widest sense to in-clude not only medical treatment and op-erations but trouble shooting, emergencyrepairs and specialized maintenance in avariety of systems, equipment and situa-tions: in fact, in all situations where theman on the spot needs immediate and ex-pert advice to tackle and complete suc-cessfully the task in hand.

CAMNET makes this possible. It is a corn-munications system that uses a headsetincorporating a miniature camera and abuilt-in screen. Transmissions from theheadset can be sent via an umbilical, orradio, or optical link to an integrated ser-vices digital network (IsDN) and thence tothe remote expert who can send back ver-bal instructions and visual data in theform of diagrams, text or pointers whichcan be viewed on the screen. But this sys-tem is feasible only where there is an ISDNchannel readily available, while expertiseis often needed in remote parts of the worldwhere no such facilities exist.

This matter has now been rectified ina joint enterprise by BTL and ABB Nera (anASEA Brown Boveri company) to developa system in which CAMNET telepresencecan be provided by satellite in any part ofthe world, however remote.

CAMNET is an acronym used by BTL forcamera and network technology. At theheart of the system is an audio visualheadset based on a pilot's standard head-set comprising earphones and noise -can-celling microphone; but one earphone hasbeen removed so that the wearer can hearand respond to local audio stimuli. Attachedto the left side of the headset above the earcup is a small CCD camera, which in con-junction with a codec can send a com-pressed video picture of the scene beingviewed via the Inmarsat A high-speed datafacility and the ISDN network to the ex-pert.

Private eyeThe headset has a miniature screen, whichenjoys the soubriquet of Private Eye,viewed with one eye at a distance of a fewcentimetres. The optics of Private Eyegives the viewer the observed effect of a300 -mm monitor at a distance of onemetre. The image is an intense mono-chrome red -on -black, high -resolution dotmatrix with a contrast ratio of 70:1, mak-ing it ideal for use in bright conditions. Thepixel resolution is 720x280 (HxV), suitablefor viewing highly detailed line drawings.The image is produced by an LED bar of 280

elements which is modulated at up to8 MHz, the image being swept across theuser's field of view by a resonating mirrorat 50 Hz.

The electronics necessary to drive theCCD camera and Private Eye are housedin a belt -pack connected to the SatCom ter-minal by a 30-m umbilical; this will be re-placed presently by a cordless link.

The expert at the base end of the sat-ellite link uses a PC terminal connected toa En' video codec and the ISDN network. Onits video display, he will view the imagetransmitted from the CCD camera on theCAMNET headset. The PC would also con-tain data for the expert to send to theheadset wearer in the field such as linediagrams, circuit diagrams, or text.

The information is converted to the cor-rect format for display on Private Eye byproprietary software running underWindows, and transmitted at the press ofa button; it is sent via the ISDN and SatCom ina dedicated area of the 64-kbit s-1 channelseparate from the audio and video.

Intrinsically robustThe Saturn Compact Inmarsat earth sta-tion is intrinsically robust and designedfor trouble -free operation. A recent mem-ber of the family of ABB Nera Saturn Inmar-sat earth stations, with over 3300 in op-eration around the world, it has a new de-sign and incorporates state-of-the-art com-ponents to save weight, space and im-prove performance.

In addition to the telepresence equip-ment, it can be supplied with a variety ofcommunications devices such as teleprint-ers, facsimile transceivers, data modems,and various types of power supply. Forthe telepresence application, as well asteleconferencing, it works in conjunctionwith a 64-kbit s-1 duplex high-speed data(lisp) system which digitizes and com-presses video material before transmission.

Three unitsThe hardware for the complete systemcomprises three units, each shock -mountedand housed in a 700x600x300 mm rug-gedized moulded polythene trunk. Twotrunks weigh 34 kg each, the third 15 kg.The trunks, which are weatherproof, areeasily portable by light transport and canbe manhandled to the most difficult sites.

The trunk for the earth station termi-nal contains all the requisite electronicsas well as a sectionalized parabolic dishwhich can be quickly assembled on sitebringing the terminal on the air withinfive minutes. The complete telepresencesystem should take no more than ten min-utes to become completely operational.

The applications envisaged for the sat-ellite system include any activity where ithas been necessary in the past to fly anexpert to the scene, engendering not only

considerable cost, but a substantial timedelay - first in getting the expert there, andthen in getting the items of equipment hehas diagnosed necessary to rectify theproblem. The potential applications are onlytoo obvious for all types of complex and spe-cialised equipment in service around theworld. Those relating to oil platforms,ships and aircraft spring immediately tomind.

Optoelectronicscommunications research

keeps Britain aheadTwo researchers at British Telecom Labo-ratories, Kevin Smith and Julian Lucek,have developed in recent months whatmay be the first all -optical signal regen-erator, a significant advance that enhancesand reinforces Britain's leading positionin optical communications. The BT teamis examining ultra -fast data processingfor the sophisticated optical -fibre net-works needed to meet the world's tele-communications demands of the next cen-tury.

Their achievement uses the results ofresearch over the past six years at theOptoelectronic Research Centre (ORC) atSouthampton University. Here, 100 sci-entists and support staff in world -class re-search laboratories sustain and advanceprevious pioneering work by promotingthe theory, basic science and technologyof optoelectronics.

Communications achievementsAs a prestigious body, ORC maintainsstrong links with industry and researchinstitutions around the world, and worksto increase the numbers of broadly-basedand highly -trained scientists and engi-neers in its field. With its established grantof 12 million over six years, ORC is cre-ating new applications for a world marketthat has grown to more than 7 billion ayear in less than 20 years. The Southamptoninitiative has been rewarded by the BTscientists' most recent development andby communications achievements in otherBritish companies such as STC, Mercuryand Cable & Wireless.

Britain is among the front-runnersstriving towards the concept of a vast in-formation network straddling the earthand providing instantaneous access tocentres of knowledge, information andentertainment. This is the Holy Grail ofmodern telecommunications, a prize soughtafter by the advanced economies. Mankind'sbig leap forward lies in communications.

Optical amplifierThe optical amplifier, the erbium -doped fibre,

ELEKTOR ELECTRONICS APRIL 1995

6

invented at Southampton in 1987, is rev-olutionizing optical communications aroundthe world. This device is considered oneof the last decade's top three inventionsin all fields and is recognized worldwideas a British discovery. The trans -Pacificlink between the US and Japan, to be in-augurated this year, will use erbium -dopedfibre amplifiers.

Britain's STC Submarine Systems is alead company in undersea and trans-oceanic communications and supplies alarge part of the world market. ThisNorthern Telecom business unit has wona contract for a system from Spain toBritain, Belgium and the Netherlands.From Spain to the UK and Belgium, thesystem is optically amplified, but the284 km between Belgium and theNetherlands is an unrepeated systemthought to be the longest in the world.

Data transmissionThe BT innovation could remove the needfor electronic amplifiers and make a sig-nificant contribution to optical sub -oceaniclinks, enabling a variety and profusion ofinformation to reach faraway destinationsaccurately and reliably. Only mode -lockedfibre lasers in ultra -fast pulses will be ableto accommodate the enormous data trans-mission demands created by the homesand businesses of the 21st century. Thissteps beyond the traditional notion of asimple pulse source and the laser is per-forming essential network functions atthe heart of all -optical processors.

The BT research team, although capa-ble of generating unimaginably fastpulses in the femto-second (10-15 s)range, prefers to concentrate on a 'morerealistic' time -scale of 100 Gbit s-1.

According to Kevin Smith: "To achievenetworks with almost unlimited range atthese speeds and beyond, we must use all -optical techniques and employ light itselfto control light, or photons to control pho-tons. Optical technology is fundamentallyfaster than the alternative - electronics -where electrons ultimately control thephotons and vice versa."

Colossal potentialMost of the BTwork covers the infrared spec-tral region and uses light of 1.3 pm and1.55 pm wavelength. The time -scales areinfinitesimally small, the distances large,but their potential is colossal. The relia-bility of the system is excellent and, com-pared with the conventional electronicamplifier, the optical system is far simpler.For the same return, an electronic systemrequires signal detection, conversion, pro-cessing and optical remodulation.

Kevin Smith's development uses er-bium amplifiers, mode -locked fibre lasersand, to support this telecommunicationstechnology of the 21st century, a wavephenomenon known as the soliton, broughtto optical reality by ORC in recent years.

A soliton is a non -dispersive opticalpulse, a pulse that in principle does notbroaden. Lasers, unlike normal pulses, cancreate soliton-like phenomena. Only inthe last few years have scientists both inBritain and elsewhere begun to see the soli -ton as a fundamental of future commu-nications technology, providing a near -per-fect, dispersion -less pulse that maintainsits fidelity while in the transmission sys-tem.

Erbium fibre13T has been pioneering the use of fibre lasers

in generating these pulses, but pulsestransmitted over thousands of kilometreswould suffer significant loss if they werenot rescued by erbium -fibre amplifiers. Thecore of this fibre is doped with ions of therare metal erbium; a laser pump sourceis used to excite them. A signal weakenedby distance along a fibre can extract thisenergy and receive gain from the excitederbium. The amplifiers, installed up to50 km apart, ensure the entire network istransparent and eliminate huge losses.

This development is revolutionizing theway engineers are starting to think of thesenetworks, allowing them to concentrate onthe data bits, that is, pulses used to com-municate information, and this is wherethe solitons come in.

Fibre lasers generate the pulses, theirsources being the same as the amplifiersinserted along the system. The use ofmode -locked fibre lasers represents onelayer of technology beyond the fibre laser.This is a very rapidly evolving field, wheremany are competing for the pulse sourceprize. In the laboratory, at the moment, themode -locked erbium fibre laser is favourite.

The capacity of soliton systems is veryhigh and in this 'shrunken -time' world,where a second is measured in hours,today's electronics can not easily manip-ulate the pulses. All -optical processing, withswitching capabilities of the order of pi-coseconds (.10-12 s), reigns supreme, atleast for the time being.

Produced and published by ELEKTOR Unit 4, Gibbs Reed Farm Overseas editions: NETHERLANDSELECTRONICS (Publishing) Pashley Road FRANCE Elektuur BV

T10EHURST TN5 7HE Elektor sari Peter Tretkpoel straac 2-4Editor Len Seymour Telephone: (01580)200657 (National) Les Trois Tilleuls 6191 VK BEEKTechnical Editor: Jan Butting or +44 1580 200 657 (International) B.P. 59; 59850 NIEPPE Editor: Baggen

Fax: (01580)200 616 (National) Editor G.C.P. RaedersdorfEditorial & Administrative Offices: or +44 1580 200 616 (International) POLANDP.O. Box 1414 GERMANY Elektor ElektrotiikDORCHESTER 1712 8YH Head Office. Elektor Verlag Gntbli 02-777 Warszawa 130England P.O. Box 75 SUsterfeld StraBe 25 Skrytka Pocztowa 271Telephone: (01305) 250995 (Natrona') 6190 AB BEEK 5100 AACHEN Editor: W. Marciniakor +44 1305 250 995 (International) The Netherlands Editor: E.J.A. KrempelsanerFax: (01305) 250 996 (National ) Telephone: +31 46 38 9444 PORTUGALor +44 1305 250 996 (internationa/) Telex: 56617 (elekt n1) GREECE Ferreira & Bente Lela

Fax +31 46 37 01 61 Elektor EPE R D EstefIni, 32-1°U.K. Advertising Office: Managing Director: Karaiskaki 14 1000 LISBOA3 Crescent Terrace Johan H. Borman 16673 Voula-ATHENA Editor F Foams de AlmeidaCHELTENHAM GL50 3PB Deputy Managing Director Editor: E. XanthoulisTelephone. (01242)510 760 Menem KJ. Landman SPAINFax. (01242) 226 626 EdItordn-Chief/Publisher. INDIA Resistor Electronica Aplica.da SA

Pierre E.L Kazemakera Elektor Electronics PVT Lid P. de la Castellana. 212-4° LidaInternational Advertising Office: Commercial Manager. Chhotani Building 28046 MADRIDEleictuurBV Karel van Noordenne 52C, Proctor Road, Giant Road (B) Editor: Agustin Gonzales BuekaP.O. Box 75 BOMBAY 4000076190 AB BEEK Distribution: Editor: C.R, Chandarana SWEDENThe Netherlands SEYMOUR Electronic Press AB'llephone: +31 46 38 94 44 1270 London Road ISRAEL Box 5505Fax: +31 46 370161 LONDON SW16 4DH Elektorcal 14105 HUDDINGE

P 0 Box 41096 Editor: Bill CedrumSubscriptions:World Wide Subscrtpttoa Sery

Printed in the Netherlands by NDB,Zoeterwoude

TEL AVIV 61410Publisher: M Avraham

ELEKTOR ELECTRONICS APRIL 1995

RS COMPONENTS INTERNATIONAL GOES CD-ROM, TOO

Preliminary details of thefirst release of the RSInternational catalogue onCD-ROM were unveiled at apress briefing at the RSheadquarters in Corby, on18 January 1995. This CD-ROM, which will be availablein March 1995, follows theresounding success of theUK version which was firstintroduced in July 1994.

Designed to assist equip-ment designers, engineersand purchasers in the selec-tion and ordering of elec-tronic, electrical andmechanical components, RSComponents Internationalhas developed a CD-ROMversion of its product cata-logue. The RS 'ElectronicCatalogue' runs on all stan-dard IBM compatible PCconfigurations.

The first of its kind andavailable free to RS cus-tomers, the ElectronicCatalogue, like its papercompanion, is updated an-nually. With over sixGigabytes of compresseddata on a single CD-ROMdisc, detailing over40,000 components, and in-cluding the RS TechnicalData Library, the user has arange of options that helpspeed up selection of theproduct best suited to an ap-plication.

Searching by producttype, the user can `browse'

as with the conventional cat-alogue, moving progressivelybetween section, sub -sectionand product group beforemaking a final product se-lection. Alternatively, theuser can search by typing ina key word, or a partial orcomplete version of the RSstock number or manufac-turer's own part number.

Containing approximately10,000 full colour product il-lustrations, the CD-ROM of-fers a unique 'virtual page'function that brings up im-ages of a range of alternativeproducts for browsing, whilea `view' function examines aparticular product in detail,displaying all relevant cata-logue data. A 'related prod-uct' function allows the userto identify products used inconjunction with the prod-uct choice.

The ordering function ofthe electronic catalogue en-ables significant time sav-ings to be made. In making aproduct selection, a stan-dard order form can becalled to simultaneouslyrecord order details of theselected item. Order formscan be archived and outputto printer or fax using an ap-propriate software/hardwareinterface.

RS Technical Datasheetsform an integral part of thenew electronic catalogue.During the product selection

The RS Components headquarters are housed in a 75,000 m2 (equiva-lent in size to ten football pitches) warehouse and office complex inCorby, Northants, England. Over 10,000 orders are processed at ter-rific speed every day at this location, including orders for the 'retail'branch of RS Components, Electromail.

RS

RS

-a.

111, millr-4

The complete RS Components catalogue (who does not have acopy?) and RS Data Library are now available on CD-ROM. Note thatthe international version of the catalogue consists of one (very thick!)book only, whereas the UK version is split into three volumes.

process, supporting in-depthtechnical datasheets can becalled up for reference, mak-ing it even easier to identifythe most appropriate solu-tion to a technical problem.

A simple start-up proce-dure ensures fast installa-tion of the electroniccatalogue, while a powerfulgraphic tutorial section andon-line help facility help toguide the user around thenew system. The CD-ROMruns on a conventional CD-ROM reader operating with astandard PC equipped with aminimum of a 386 proces-sor, 4 MB RAM, Windowssoftware and VGA screen.For enhanced operation, a486 -based system with anSVGA, 256 -colour screen isrecommended.

The international versionsof the CD-ROM cataloguewill be available from March

1995 in Europe and the restof the world, with country -specific introductory sec-tions ensuring customersreceive distribution and con-tact information relevant totheir market. (950059)

Further information fromyour local/national RSComponents distributor, orfrom RS ComponentsInternational, P.O. Box 99,Corby, Northants NN17 9RS,United Kingdom. Tel. (+44)1536 201234, fax (+44) 1536401096. Telex: 342512.

ELEKTOR ELECTRONICS APRIL 1995

8

FUNCTION GENERATORDesign by H. Bonekamp

A simple function generator is described, which providesrectangular, triangular and sinusoidal waveforms in the

frequency range d.c.-100 kHz. In contrast to many 'simple'function generators, it provides a fairly good sine wave.

Alsmost all function generators con-ist of a variable -frequency, rectan-

gular -wave oscillator that provides anumber of switch -selected frequencyranges. Its output is applied to an inte-grator which converts the rectangularwaves into triangular ones. Finally, thetriangular waves are converted to 'sinewaves' by soft clipping with a diode.

The present generator is no excep-tion as is shown in Fig. 1. The triangu-lar -to -sine wave converter is based ondiodes and has an output voltage of5UD, where UD is the forward voltage ofone diode. It can be shown that for cor-rect operation, the converter needs aninput of (n/2) x 5UD.

Moreover, the diodes in the con-verter make it necessary for the inputvoltage to be temperature -compen-sated. This is assured by limiting theoutput of the comparator to 1 UD by twoanti -parallel connected diodes. This israised to a level of 5UD by the amplifier.

The 1:0.5n ratio of the feedback re-sistors ensures that the input voltageto the triangular -to -sine wave con-verter is (n/2) x 5UD as required.

Circuit descriptionIn Fig. 3, the comparator of Fig. 1 isformed by ICib. Capacitor C2, shuntingR2, compensates for the delays causedby op amps ICia and ICib, so that thelevel of the output voltage of the rec-tangular -wave generator remains fairlyconstant up to 100 kHz.

Capacitor C1 decouples R1 for h.f. toprevent the input capacitance of ICibhaving an adverse effect on the waveshape.

Resistor R1 compensates for the off-set error caused by the bias currentthrough R2 -R3.

The limiter consists of anti -parallelconnected diodes DI and D2. These arefast types to ensure that the circuitquickly operates correctly. Since thelimiter should operate symmetrically, itis important that the diodes arematched.

The amplifier is formed by ICia. Thisis an op amp with a fairly high slewrate (300 V ps-1) which is essential fora well -shaped voltage at frequencies up

to 100 kHz. Its amplification isarranged at exactly x5 by R5 and R6.

Frequency control of the oscillator isobtained by driving an integrator, con-sisting of R8, IC2b and one of capacitorsC3 -C7, with the rectangular wave. Theop amp ensures that the capacitor se-lected with SI, is charged or dis-charged at constant current. This givesrise to a triangular voltage. The speedat which charging and dischargingtakes place depends on the capaci-tance and the applied voltage. Thevalue of each of capacitors C3 -C7 dif-fers by a factor 10 from the precedingone. Switch SI, which selects one ofthe capacitors, thus provides subdivi-sion of the frequency range into five.

The triangular voltage is applied tothe non -inverting input of ICib and de-termines, in conjunction with the out-put of the x5 amplifier, the exactchange -over point of the comparator.

The triangular voltage is available atthe output of IC2b. Since it is importantfor the integrator that the bias currentis as low as feasible, IC2 is an op ampwith (high -resistance) JFET inputs.The low slew rate does not matter here.

The peak value of triangular voltageis, as explained earlier, 0.5n higherthan that of the rectangular wave. Toensure that these level differences donot have a deleterious effect duringswitching from rectangular wave to tri-

ParametersFrequency ranges:

1 Hz - 10 Hz10 Hz 100 Hz100 Hz - 1 kHz1 kHz 10 kHz10 kHz - 100 kHz

Functions: rectangular, triangular,sine wave

Rise time (rectangular wave): -0- -0j)

950044 - 12

V

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Fig. 1. Principle of a function generator.

ELEKTOR ELECTRONICS APRIL 1995

FUNCTION GENERATOR 9

Fig. 2. How the sine wave is shaped.

The three output signals are appliedto FUNCTION selector S2. Circuit IC3 am-plifies and buffers the selected outputsignal. The amplification is set to x3.5by R15 and R16, so that the output volt-age can be adjusted with P4 between0 V and 20 V The output impedanceis fixed at 600 52 by R17.

The symmetrical power supply fol-lows the usual pattern of mains trans-form, bridge rectifier, buffer capacitorsand two voltage regulators, IC4 andIC5. Since the circuit does not drawmuch current, the specification of thetransformers and buffer capacitors ismodest.

ConstructionThe generator is intended to be built onthe printed -circuit board shown inFig. 4. Note that the transformer,switches and preset controls aremounted directly on to it.

It is advisable to adhere strictly tothe components and devices specificedin the parts list. Many resistors have atolerance of not more than 1%.Capacitors C3 -C7 should be good qual-ity types; do not use an electrolytic ca-pacitor in the C3 position, but a poly-propylene or polyester type.

Diodes D1 and D2 should bematched. Instead of buying two, buyfour of them. From these, select the

two whose knee voltages are identicalor very nearly so. This is ascertainedby connecting the diodes in series withan 8.2 kS2 resistor to a 12 V d.c.source, and measuring the drop acrosseach diode with a digital voltmeter. Donot touch the diodes during the mea-surement and make sure that the am-bient temperature remains constant:small differences in temperature canhave a large effect on the measure-ment.

The same applies to the 1N4148diodes for the triangular -to -sine waveconverter. Using the method just de-scribed, select ten with an identical ornear -identical knee voltage. Fromthese, select five pairs that are identi-cal: D3 -D4; D5 -D6 D11 -D12.

The completed prototype board isshown in Fig. 5. This is readily fitted inan 80x200x132 mm enclosure-seeFig. 6 -with suitable spacers. A sug-gested front panel (a photo copy ofwhich can be used as a template fordrilling the front panel) is shown inFig. 7.

R2

5

6

rn

co

C

68pR3

C1

Tn

TR1

IC1 = AD827/JN1C2 = OP249GP

10k0

-01 02

R6

-177071-0

R5

2x mi.1N4151

4x 1N4001

IC1a

IC4

105

13 i4 15 16 171p5 7

5

5 150p4

(:). 0-1 6

Si

A

R8

10k0

P21klin

R7

IC2b

15V

S22

R10

R9

1 k00

D3 05

R11

D7

IC2a

D9 D11

R16

P410k -lin

C13mim

:100n

R15

IC38

4

AD847JN

:17700n

® 15V

R17

60452

K1

O 15V950044 - 11

Fig. 2. Circuit diagram of the function generator.

ELEKTOR ELECTRONICS APRIL 1995

10 TEST & MEASUREMENT

TR1

"... K2

950044-1

C8

Calibration

10

01 1

Ra

amt2

Z10( R2 I°1-t

0 ; Lt71:4r

P2 '3/4 - od1-

C5

1C4

cia°UK°03 K1t

0 I

Fig. 4. Printed -circuit board for the function generator.

There are two calibration controls: P1and P3. The former sets the operatingpoint of the limiter, which is importantfor the production of the third har-monic of the sine wave; the lattercauses a small offset correction voltageto be added at the input of op ampIC2a, which affects the second har-monic. A spectrum analyser makestheir setting easy: adjust them (at1 kHz) for minimum amplitude of thetwo harmonics.

Where a spectrum analyser is notavailable, calibration can be carriedout with a dual -channel oscilloscopeand a digital voltmeter.

Apply one channel of the scope tothe junction R6 -pin 1 of IC la, and theother channel to junction R12 -R13 -R14.Connect the scope's earth to junctionRTP2.

Switch on the generator and the os-cilloscope and set the generator to1 kHz, whereupon channel 1 shows therectangular wave and channel 2 thesine wave. Adjust the attenuators and Fig. 5. Completed printed -circuit board.

ELEKTOR ELECTRONICS APRIL 1995

FUNCTION GENERATOR

Fig. 6. Completed function generator with top cover removed.

X/Y controls of the scope so that bothwaves fill the screen and cover one an-other. Then, adjust P1 until the ampli-tudes of the two waves are equal.

Set the digital voltmeter to the directvoltage range and connect it across theoutput of the function generator.

Turn P4 fully anticlockwise and notethe reading on the voltmeter: this isthe offset voltage of IC3

Turn P4 fully clockwise and adjustP3 until the voltmeter reading is thesame as in the preceding paragraph.

Parts listResistors:RI = 6.19 kS2, 1%R2 = 15.8 1.(52, 1%R3, R8 = 10.0 k52, 1%R4, R9= 4.7 kS2R5, R10, R14 = 1.001d2, 1%R6, R13 = 4.02 k52, 1%R7 = 82 CIR11 = 470 IcI2R12 = 2.43 kcI, 1%R15, R18 = 6.8 Ic4R16 = 2.7 IcC2R17 = 604 52, 1%P1 = 10 ki-2, preset

P2 = 1 ki/, linear potentiometerP3 = 100 Id2, presetP4 = 10 kf2, linear potentiometer

Capacitors:C1 = 1 nF, polypropyleneC2 = 68 pF, ceramicC3 = 1.5 pF, polypropylene/polyesterC4 = 150 nF, polypropyleneC5 = 15 nF, polypropyleneC6 = 1.5 nF, polypropyleneC7 = 150 pF, ceramicC8, C9 = 1000 pF, 25 V, radialC10, C14 = 10 pF, 16 V, radialC11 -C13, C15 -C17 = 100 nF

Semiconductors:D1, D2 = 1N4151 (matched - see text)D3 -D12 = 1N4148 (matched - see text)D13 -D16 = 1N4001D17 = LED, high efficiency

Integrated circuits:ICI = AD827/JN (Analog Devices)IC2 = OP249GP (Analog Devices)IC3 = AD847/JN (Analog Devices)IC4 = 7815IC5 = 7915

Miscellaneous:K1 = BNC connectorK2 = 2 -way terminal block, pitch

7.5 mmS1 = 2 -pole, 6 -position rotary switchS2 = 4 -pole, 3 -position rotary switchS3 = mains on/off switchTr1 = mains transformer, secondary

2x15 V, 3 VA (Velleman 2150038M -Maplin)

Enclosure 80x200x132 mm(31/8x77/8x53/16 in)

PCB Order no. 950044-1*Front panel foil Order no. 950044-F** see p. 70

0500441

0

POWER3

2

1

x 10kHz

FREQUENCY x lkHz

5 64 7

x 100Hz

x 1014z

8 x 1Hz

9

10

FUNCTION GENERATOR

RANGE

FUNCTION

10V8V,....r.,j2V OUTPUT6V 14V

4V 16

2V 18V 60062

LEVEL OV 20Vpp

950044-F

Fig. 7. Suggested front panel for the function generator (true scale).

ELEKTOR ELECTRONICS APRIL 1995

Please mention ELEKTOR ELECTRONICS when contactil g advertisers

, ,

12" : ' "1 V9338

INTEGRATED

lEWCOVICOM G FAX 0181-552

CIRCUIT SPECIALIST

0946

7490589 0.927460590 1.207480592 1.247480593 1.897460595 1.147460597 1.107460620 1.82746C623 1.487460633 POA7480640 1.367460643 1.367460646 1.88

74607237 1.2074607238 0.6974607240 0.5374HC7241 05874HC7242 1.2474607243 1.2474607244 0.5474607245 0.5474607251 1.1174607253 1.1174607257 1.1174607258 1.11

74810 0.2874611 0.2874613 POA74614 0.3674F20 0.3974F27 0.4174630 0.2874F32 0.2874F37 0.5174F38 0.4474640 0.9474651 0.94

7440251 06074A0253 0e07440258 0.607440273 1.107440283 1.407440299 2.067440373 0.9474AC374 0.9274AC377 0.98744C521 POA7440540 2987440541 028

791264 0.987915 0.687918 1sa7924 1.60797124 0.2879M05 0.9879M054 1.8279M12 1.8279M124 1.82L4805CV 3.40L4940V5 6.40LM317MP 0/8

354/100V/Sqr 2.98KBPC1002 1.64KBP03502 298W005 -14/50V a32W02G-1.54 0A02W02 0402K8010R/SIL 0.662KBB2OR/SIL 0.70B8001500/Sqr0.35B80C1500SIL 0.60SKB6008/604 POASKD6008/604PO4

Freq.= MHz1MHz £8.90 ea.

4 4 9152 6 8 9 8304. .

10,12,15,16,19.660818.432

24 25 &20"30MH7

price: £3.52 ea.

32,

40, 50 632.768,66MHz33.33,

8M4402564Z-10 6.95M5M4464P-15 4.60MK41169-54 noMK45649-15 194NMC3764N-15 1.60UPD41464C-12 4.20UPD41464C-15 4200004160-2 3.40UPD4160-3 3e5UP0446D-1 2.60

STATIC RAM

TEL 0181-471

DIGITAL

TLX 929709

7460648 1,88 74607259 1.24 74F64 1.24 7440573 128 LM3 1 71 0.78 CRYSTALS74110651 1.497460652 2A0

74607273 1.2474607280 1.29

74F74 0.3174F85 2.24

7440574 1.387440646 POA

LM338K 4A5LT1084075 622 HC49( HC18/U)

Price: £4.45 e0. 2114-35 3.406264LP-10 2.7045118 044

401687 0.43401767 0.78

74175 1.1074180 1.16

741_0189 2.817470190 0.54

74LS693 POA74LS794 POA4000 SERIES

40008 0.18400008 0.18400113 0.184001UB 0.2240028 0.18

45128 0.664513B 56045146 1.124515B 1 1245166 0.44

401887 0 78402087 0.95402167 0.65402387 0.38402487 0.76

74184 POA74185 1.7674191 1.2674192 1.41

74L0191 049741_0192 0.5474L0193 0.4874LS194 0.5474L01944 0.54

74LS795 POA741_8796 POA74LS797 POA74L0848 POA81LS954 1.25

746C658 POA7490659 POA7460664 POA7460665 POA7460670 1.15

74607283 06474607297 1.4874HC7299 1.6874HC7354 0.7474607356 1.54

74686 0.34746109 0.58746112 0.6374F113 POA746114 POA

744C648 POA LT1085075 6.600C41959 2A07L7830K0 628

Freq.MHz1.843200 1.602.000000 1.662.453200 9.962.457600 1.49

ProgrammableCrystal

Oscillators

DM -3C SERIES8pin DIL Plastic

6264LP-12 2.7062256LP-12 4.95622564P-10 4.95CDM6116AE3 5.30CDM6117AE3 5.85

74000 0.5074CO2 0.5074008 0.50

DIODES

40068 0.424007UB 0.2440088 0.4240286740094E 0.264009UB 0.2940106 0.297404240118 0.284011UB 0.2840124E 0.20

45178 1844518B 044451913 0.3645208 0.444521B 0.6445228 0.864526E3 0.6045275 0.58

452813 0.4945258 0.74

402567 0.38402707 0.45

0.56

4029611 ass4040137 a70404287 0.74404687 1.41404707 1.06404967 1.06

74193 1.6574221 2.40/4259 2.9274265 1.4674273 POA74276 5.1879279 POA74283 POA

74365 POA

74LS1 954 0.56741_0196 POA7475221 0.4674LS224 10.3074L0240 0.487470241 0.48741_0242 POA74LS243 0.507449244 0.48

81LS974 1.257460677 POA741-10678 POA741-10680 POA7460682 POA7460684 POA741-10680 0.747460690 1.627460691 1.827460692 1.82

1.82

74807365 1.2874607366 12474607367 0.5974607368 1.2974607373 0.5274607374 0.5274607377 0.6574HC7390 0.68746C7393 0e874607394 POA

746125 0.56746126 POA746132 ass74F138 0.58746139 0.58746148 POA746151 1.4774F153 0.58HM6264A5P.20746157 0.56746158 080

74010 05074014 POA74020 0.5074030 0.5074032 0.50

1.7874046 1.8474073 1.6874074 0.89

19298613018.201N3881 2.541939974 6.55I N4001 0.041N4002 0041N4003 0241N4006 0.04194007 0.04194148 0.03

3.276800 0983.579545 1.103,686400 1024.000000 1.024.096000 1.104.194304 1.104.433619 1.104.608000 1.104.915200 1.205000000/8 1.02

MHzFreq.= MHz12, 1A31d18, 16,15384,19.6608 820MHz

Price: £3.92 ea.

16pIn DIL Plastic

HM1.6116-5 4.38HM3-6116-5 3.60HM6116LP-2 assHM6116LP-3 2.60HM6117LP-3 5.75HM62256LP-10 793HM6264ALP-12 3.95

3.95HM6267P-35 5.92

74HC SERIES7411000 022746002 0.22746003 0.28746004 0.227460004 0.24746005 0.32

40128 0.224013B 0.2240148 0.42

4530B 2.247407645318 1.1845328 0.86

4050E17 0.46405107 0.784052137 0.84

74367 POA74393 4.8974403 POA

741_3245 0.507412247 POA74LS244 POA

746007 0.4874HCO8 0.22746009 0.48

74606937460696 1.827460697 1.82

1.42

74807423 0.8274607533 1.6374607534 0.75

746160 0.907461604 POA74F161 098

1.1474085 1.6674090 1.16

1N4149 0.06194150 0.08194446 D.06

5.068800 1.105.242880 1.205.688200 190

Package1,,

57 0i0.Frequency

HM628128LP-801794

HM66204L-12 15.80

40158 0.4240168 0.28

4534B 2.8245265 1.08

4053BT 0.98406081 0.84

74423 POA 74LS249 POA74L0251 0.00

746010 0.29746011 0.22

74606987460699 1.62 74607540 0.66 746162 POA 74093 1.63

740150 3.481947284 0.241947354 0.24

6.000000 1026.144000 1.02

SPG8640490.005 to 600kHz

KM62256ALP-10 495LH5164D-10L 2.40El1=11

741_000 0.1840160130.26

40178 0.3845386 0.6045398 0,2

406687 0.59406867 0.38

74LS253 0.0074L0256 POA

746014 0.267460144 0.36

74604002 0.4874604015 1.07

741-107541 0.74741-107563 1.46

746163 0.88746164 0.88 740151 POA

740154 4.881947364 0.241947404 0.24

6.400000 1.641.40

SPG8640BNP0D5101P 3.30UPD43256AGU1OL

40188 04640198 0.2840204E 0.36

45418 0.5645438 0.57

3.52

40690131 0.38407007 0.38407167 0.38

741_001 02474LSO2 0.1874LS03 220

741_0257 000741_0257A 0.4874LS258 1.00

746020 0.24746021 0.24746027 0.24

74604016 0.5874604017 ass74604020 0.52

74607564 1.6774607573 0.7474607574 0.74

746166 3.82746168 POA74F169 3.60

740157 3.02740164 1.91

1N4743A 0.241947444 0.241144756A 0.24

6.5520006.553600 1217.372800 078

0.0083 to 1MHz

SPG864009t 768kHz

8330PD432560-12 5.60UPD4364C-15 4.70

4020B 0.3840218 0.40

4544845478 3.2545498 7.50

407567 0.38407707 0.38

741_804 0.21741_505 0.21744506 0.51

741_02584 0.4874LS259 POA

746030 0.24746032 0.24746042 0.54

741-104022 0.7474604024 0.6274604028 0.58

74607583 1.4874607597 1.5274607640 1.34

746174 0.80746175 0.8074F181 6.85

740221 2.54740240 1.38740244 1.38

195226B 0.141952328 0.14

8.000000 1.008.667230 1.349.830400 1.20

aed6R4at:Generator

560865013N UVPROMS40220 0.404023B 0.20

45518 1.6245538 2.95

4078131 0.38408167 0.38

741_007 0.51 74L5260 POA741_0266 POA

741-1051 0.32 74604040 0.48 74607643 1.97 74F182 POA 740373 1.38 1952348 0.141953370 0.98

10.00000 1.10 0.00083 to 100kHz270128-25 3.95

402308 0.2340244E 0.3040248 0.32

45546 POA45555 0.82

4093137 0.454094137 0.95450867 2.05

741_808 0.1874L009 0.20747010 0.18

7475273 POA741_0275 POA74LS279 0.35

746058 0.54746073 0.38746074 0.28

74604046 1.447460404641.90741104049 0.46

74607646 2A074607648 6.4074607651 POA

746189 4.40746190 POA746191 2.92

740374 1.38740901 0.94740902 0.94

1953490 0.981953526 0.98

10.69500 1.9011.00000 1.1012.00000 0.92

P00-6000.005 to 600kHz

P50-1000

27C64A-15 3.95270256-15 3.95270256-25 3.95

40256 024402508 ass

45568 0.8245578 1.98 4510137 1.02

4511B7 1.35

74LS11 0.1874LS12 0.16 741_8280 0.8674LS283 0.457409077460744 0.287411075 0.48 74604050 0.3874604051 0.74 74607652 POA74607670 1.10 746192 POA74F193 2.92 740903 POA740906 0.94 11153578 0.9819536513 0.98 13.87500 aao14.00000 1.64 0 0083 to 1MHzAll 2705120-12 6.482701000D-12 992

402613 0.9440278 0.3040286 0.384029B 0.39

45558 2.5445608 1.6245616 1.964562B 5.8245666 1.111

451287 0.68451487 2.20451681 1.02451413T 1.18

74LS13 0.2474LS14 0.2474L215 0.3874L020 0.20741_521 0.20

74L0290 POA74LS292 14.5874LS293 0.42741_0294 1A58

746076 0.48746C77 0 52746C85 0.52746086 0.30

74904052 0.7474604053 07474604053471274604060 0.46

74607673 POA74607688 1.10746C74002 0.39746074015 1.41746074016 as2

74F194 1.36746195 2.00746219 POA74F224 POA

0.94740908 1.51740911 13 98740912 13.98740914 0.94

1 953660 0.981953700 0.9819538013 ass195401 0.111N5402 0 11

14.31818/S 0.8514.74580/S 1.101474560 1.1015.00000/S 1.1016 00000 1.02

Price: £ 9.25 ea.

OS.P0 OG088635 to 100k6427010240010Cal. Tol. 5pprriPrice: 0 10.50 ea.

2704096-12 POAHM27C1016-20 9.80

16.63

40308 0.3440318 1.24

45558 54245698 3.04

4520BT 1.184521131 1.07

74L522 0.24741_024 0.68

741_0295 POA74LS2954 POA

746093 0.487460107 0.487460109 0.46

74604061 POA74604066 0.507460406640.58

746014017 0.68746014020 074

746240 0.60746241 0.60746244 0.60

740915 2.24740922 5.60

1 N6287A 1.551 N825 2.98

16.00000/S 1.2014A3200/8 1.10

4427C64FP-20T 3.406427064G-15 5.60DC to DC

4032B 0.7040338 0.68

45720B 0.844573P 6.98

4522137 1.22452887 0.88

741_526 0.2074LS27 0.20

74LS294 POA741_0299 1.76

74110112 0.507460113 0.54

741104067 4.72741-104072 0.48

746014024 0.68746014040 0.70

746245 0.6674F251 POA

740923 6.28740925 8.40

198254 2.9819827 3.42

19.66080/S 1.2020.00000/S 1.60

Converters 141427C64G-20 56069462532P 4.50

40346 2.10403513 0.5240368 2.9840378 1.27403813 0.784039B 3.2240408 0.42

4580B 8.8445818 P0845828 pa,45830 1 384,640 0 584,850 07445978 6.60

4534BD POA4538811 1.05454187 1 05454387 1.024555137 POA4556B7 1.054585137 0.95

74LS28 0.24747030 0.1874LS31 1.5827.64800/S74LS32 0.2074LS33 0.60741.037 0.20744038 0.18

74L0321 3.297475322 POA74LS322A 60874LS323 POA74LS347 POA741_0348 POA74LS352 POA

7460123 0.42744C123A D.427440125 0.42744C126 0.45746C131 0.527440132 0 607460133 0.44

74604075 0.4474604078 0.4674604094 0.7874604316 0.7474604351 1.0574604352 1.6274604353 1.62

746074046 2.10748074051 0.96746074052 0.96741-1074053 0.84746074059 2.24746074060 0.84746074066 0.66

746251A am746253 POA746257 P0A,7462574 0 5674F258 POA746259 POA746260 0.76

740926 8.40740929 POA80095 0.7680098 0.98

100252 0.205082-2800 0.665082-2810 2.475082-2835 0.6844119 0.60A4144 0.7244Z15 0.58

22.11840/S 1.6824.00000/0 1.82

1.2030.00000/5 6.9932.00000/5 1 4048.00000/S 1 96s series

TDK 0E-0344 5.603W5R 15-15 27.50IPL 0.010 23A0

1 Watt DC/DC5V input -,-Output

DIL 8 SIL by

694827128G-25 4.551-19482764G 390m27164 pi 250M5L2732K 4.40M5427641< 3.30MBM27064-20/21V

4.90745 SERIES74500 0.684041B 0.48

4041UB 0.4840428 0.3840438 0.3940448 0.3940458 1.10404613 0.44

45858 7.4045225 5.8247208 POA4720V POA4723B POA4724B 0.98422( (4

4010607 0.534024467 1.354037387 2.34

744040 0.1844Z17741_042 0.32741_544 2.11744547 0.68741_548 0.64744S49 POA

74L-5353POA

74LS363 POA741_5364 POA

741-0365 -74L03654 0.54741_0366 POA741_83664 POA

7460137 0.727460138 0.3474HC139 0.3274H0141 POA7460147 0.687460148 0.72

74604511 0.8474604514 1.1074E104515 1.8574604518 0.8774604520 0.7874604534 POA

746074067 5.78746074075 0.36746074094 084749014316 0.68746074351 1.04746074510 1.54

74F269 5.5474F273 0.96746280 0.70746283 1.00746299 POA746323 POA

74502 0.6874003 0.780.20480074504 0.6874808 0.6874009 0.6874810 1.10

0.584218 0.4808010A

0.12BAV45 4.98BAW62 0.06134016 0.0800204

HC33/U823

0.307200 6.991.000000 3151.843200 3.712.000000 455

NewportNMA050555VNMA050959VNMA0512512VNMA0515515VPrice: £ 13.0580.

MBM270126-30 4.20MBM27C256-30 5.10NMC2702560-25

4.95NMC27C640-25 3.66TMS2516JL-45 4.58TMS27128JL-25 4.60

74 SERIES7400 0.367401 0.30

40478 0.4440488 0.8240498 0.304049UB 0.2840506 0.2840618 03440528 0.3340530 0.36

- 8 - 9.804737,p 19.604738VP 19.74475000 28.504752VP 29.2547550p pa,26.704754VP 60840085 POA40097 0.68

7402 0.327403 0.327404 0.347405 0.347406 0.687407 0.817408 0.377409 0.387410 0.35

741_051 0.22744054 0.28744855 a4474LS73 a35744573A 0.79744274 0.20744574A 0.26741_575 0.25744S76 POA

741_8367 0.36741_03674 0.36741_0368 02674703684 POA

741-0373 0.48741_0374 0.48741_5375 0,42,,,7413377 "'"-

7490151 0.407460153 0.4274110154 0.627460155 0.727460157 0.427460158 0.5474140180 0.7474140161 0.42

74604534 0.6874604543 09874607001 1.01741107007 0A274607032 POA74607074 POA74607240 0.9874607241 0.98

746074511 0.94746074514 1.64746074515 181746014516 POA746074520 0.90746074538 1.02746077007 0.39746077038 5.40

746350 POA74F352 POA746353 POA746365 POA746366 PO4746367 1.42742368 POA74F373 0.60

74811 0.682.09715274020 0.6874S32 0.6874038 0.6874540 0.2574551 0.3674064 0.3674074 183

0.448821 2 2.94BE1405E1 0.33

80805 05087179 0.74BY260-200 3.58BY261-200 3.98BYV28-100 0.9980032-50 1.60

3.712.457600 1922.500000 la23.000000 2.25

HC49(U463.2768 00 1.66

'1' '1 O 1.585.068800 2.25

DC/DC Convertersby Computer

ProductsPM623PM671

24.60

PM672 26.70PM903 4400PM951 46.50

TMS2716JL-45 4.60UPD272560/21V 5.60UPD27324/21V 4 95UPD270256D-15 580UPD270512D-15 596UPD27064D-25 4.95

EEPROMS40548 0.7940558 0.8240566 0 82405913 31540608 0.38

40098 0.6840100 POA40101 PGA40102 1.8640103 1.14

7412 a647413 0.767414 0.647416 0.48

744S76A 1.05741_577 0.4474L578 0.3274LS83 0.39

741_0378 POA741_5379 1.5074L5381 A PO474L5385 60874L0386 POA

7440162 0.747460183 0.427440164 0.427460165 0.557460166 0.86

74607244 0.9874607266 0.6674607292 1.1074607294 1.1074607640 1.98

74H017046 2.807460140102 2.437490140103 1.487460740104 POA

748374 0.60746377 1.3474F378 2.72746381 5.7074E385 POA

74086 0.83745112 a90745124 3.13745132 1.11743133 0.80

CV8805 0.60DS160 0.40M01404 15.90MV209 1.8204200 0.84

' 964920 1.498.000000 1.1410.00000 25211.05920 2.4012.00000 1 14

RESISTORS28064-25 9.8028064-15 10.95280256-20 18.40280256.15 19.60

METAL FILM0.25W 1%E24 Series74HC SERIES

40635 0.58 40105 POA74170 4874 0.37

744S83A 0.39741_085 0.36 74L5390 ---

7440173 0.767460174 0.42

74607643 1.9874607645 1.98

SURFACE 746395 POA746399 POA

748134 2.157401313 0.97 04202 0.84

14.00000 2.25 100 to 1M 280256-1513C 29504066B 0.274067B 2.284068B 0.28406906 0.2240700 0.224071B 0.2240725 0.2240736 0.2840758 0.2240768 0.6440778 0.28407013 0.2840816 0.224082B 0.2240856 0.564086B 0.564089B 0.9840938 0.264094B 0.38

40106 0.3240107 0.4240108 POA40109 1.2440110 1.6240114 3.4040116 POA40117 POA40147 1.2340160 0.9240161 0.5440162 0.7240163 0.7240174 0.4240175 0.4240181 POA4019240193 0.7440194 POA

74251.107426 0.487427 0.597430 0.357432 0.457437 0 547436 0.467440 0.777442 0.547445 1.127446 1.387447 0.9874474 1.407451 0.577454 0.727470 0.547472 0.387473 0.587474 0.53

744386 0.26741_090 0.32741_291 POA744592 POA744093 0.40741_595 0.48741_696 0.8274LS10774LS1074 0.78741_5109 0.3374L01094 0.66741_5112 0237455112A 0.6674LS113 0.3674LS1134 0A274L0114 0.36741_01144 0.40741_5122 0.337472123 0.35

741_8393 0.4274LS395 POA74L03954 POA7475396 POA741_5398 POA741_0399 0.92741_5423 0.98741_5445 POA74L0450 10.64741_5461A POA74L0465 4.1874L0467 POA7470468 POA741_0469 POA741_8490 POA74LS4914 POA74LS540 ass741_0541 0.80

741-S569POA

7460175 0.367460181 1.947460182 0 597440190 0.887460191 0.687460192 0 787460193 0.767460194 0.787460195 0.787460221 0.587460237 0.767460238 0.647460240 0467460241 0.787460242 0987460243 0.987480244 0.4874110245 0.48

746040102 1.32746040103 1.12746040105 1.42

MOUNT748412 POA746413 POA74F432 POA74F521 1.05746524 POA746533 POA746534 P08746537 POA746538 POA746539 POA746540 POA746541 1.98746543 3.5774F544 P08746545 P08746547 PO746573 2.78746574 2.78

740139 0 97740140 1.02740153 1.39740157 1.89745163 279740174 1.01745175 1.49740182 3.62740169 2.35740195 2e4740240 2.31740241 2.31745244 1 95740257 1.34740258 124740260 0.7774S273 2.68740274 2.66

0A47 0.140490 0.14P6KE313A 0.99P6KE47A 0.99REC534 0.92ZP02.7V 0.06

ZENER DIODESMISC.

BZY9307V57.401321(93C15 7.40BZY9301887.40BZY93C20 7.40BZY93024V7.40BZY93033R7.40BZ7030120 0.74BZX61C9V20.0982/C610241/0.09

16.00000 1.14m000sa 1.9224 00000 1 90

- '

UM -1

8.000000 2.258.192000 2.021000000 2.2511.00000 2.251228600 2.661500000 2.2517.73447 28012.00000 2.50

moo= 2.2521.00000 22524 00000 290

CRYSTALS MISC.

Pack of 5 - 15pPack 01 10 25p

METAL FILMPRECISION

0.25 WATT 0.1%E96 Series

10011 to 255KPrIce: £0.94 each

HIGH PRECISIONNON -INDUCTIVEWIRE WOUND

0.15 WATT 0.1%

'eme-cea-ea'10R,50R,100R,2508,10K,100KPrice: £3.85 each

X281640X281640-25 5.10X286440-35 122024C01 1.62

24002 2.1024004 2 9824016 54028C04A.20 4.4059C11 1.4493C06 1.1293046 1.2893056 1.5293066 2.16

MISC. MEMORIES

6341-1J 4.588M2148 -450C 5.448M275281PC 3.98

74HCOOM 0.32746002M 0.327411003M 0.32746004M 2327460004 0.32746008M 0.32746010M 0.32746014M 0.36746020M 0.36746030M 0.36746032M 0.367460744 0.36746075M 0.34741-1085WM 0.65746086M 0.3674HC123AM 0.467460125M 0.467460132M 0.42

74HCT SERIES

74110702 0.247490103 0.28746C704 0247460708 0.247460710 0.247460711 0.247460714 0.287490120 0.287460721 0.287460727 0.28746C730 0.287460732 0.287480742 048

4095B 0.7040556 1.1040978 2.75

40195 POA40240 POA40244 1.36741-107757475 0.647476 0.647480 1.26 74L0125 0.2874LSI 254 0.32741_5126 0.32 74LS573 1.0274LS574 1.025.09

74602454 0.54741-10251 0.367460253 0.527460257 0.52

7460773 0.387460774 0.28

0.38

7460138M 0.387480139M 0.3874HC154WM 0.64

746579 6.59748604 5.59746620 POA748621 POA

740280 1.06740283 2.09740374 2.3174S394 2.31

ZENERDIODES400mW

HC43/T1.000000 6.99

MINI CYLINDER

HIGH PRECISIONNON -INDUCTIVE

IDT7130LA-100P 10.4010771321_4-1000 12.20MB8414E 495

4098B 0.8440995 042

40245 1.3640257 0.05 7483 1.10 74L51264 0.40

74LS592 5.09

74LS5,49'7.21020 73 74601185 0.54 74HC157M 0.38

74110161M 0 48746623 POA 74S412 2.31 2AV to 75V 0.032768 0.88 WIRE WOUND

0.33 WATT' 0.1%MCM4027AC3 2.806825099 POA

4104P 1.01 40373 1.34VOLTAGE7485 0.58 741_0132 D.29 74h07; 7460259 0.52 7460786 0.387460793 0.60 74HC164M 0.48 746646 Price: 6p each WATCH N62S126AN 249REGULATORS4106B 0.88 40374 1.34

7486 0.537490 0.72

741_5133 D.35741_5136 D.78

,7,cnc

741-5- 77-741-10266 a487460273 0.54 74607107 0.40 74601 65M 0.57

746676 3.22746821 POA ZENER DIODES

0.032768 0.82TemaCoeff.3ppm 98281535 580

41606 1.4041610 1 20

45026 POA45027 5.gg 7490A 0.72

7491 2.56744S137 1.58741_5138 2.34

741_5621 POA74LS622 POA

7460279 2587460280 0.92

741-107109 0.4274607112 0.42

7460173M 0.487460174M 028

746623 POA746625 POA

78008AP 1.347805 0.44

500mW2AV to 200V

CRYSTALOSC. MODULES

161,5R,1061,20R,5061

Price: £3.60 each982S -1814N 509NM06504.1-9 140

41638 1.2041745 1.20417513 1.144194B 1.43

45022 pa,45040 POA45041 71044,100 1.56

7492 0.677493 0.607493A 0.607497 4.48

7475139 D.42741_01394 D.4274LSI 45 0.6674L0147 POA

74LS623 POA741_5624 2.10741_0625 POA741_0626 POA

7480283 0.7674140294 12974410298 2787460299 1.38

74607123 0.6474607125 0.5674607126 0.5474607132 0.50

7460221AM 0.6574HC240WM 05574HC244WM 05574HC245AW 0.62

746827 3.32746841 151

76054 .68700564 0.987806 0.887806 1.34

Price: 6p each

ZENER DIODES1.3 WATT

Spin DILPlastic pkgTTL Output

100R,120R, 250R,500R,IK, 2K, 5K,I OK,20K

NMC93069 14505101 L-1 190TBP185030N 174TBP24S10N 29074AC SERIES4409P 11.05

4410P 16.454411P 21.58

45106 pa,4,105 pa,45145 13.96

74104 0.6774107 0 6074110 POA

74L0148 0.8774L0151 ass7412153 0.36

741_0628 1.7874L0629 2.25

7460323 1.827460352 1.20

74607137 0.5474607138 0.3274607139 0.52

74HC251M 0.427460259M 0.6974HC273WM 0.55

7809 0.727812 0.6878124 0.98

2.70 to 200VPrice:10p each

4 Pins spaced at

cereaCorners of BpinDILFreq.= MHz

Price: £3.10 each TBP245410N 3.19705501P 1501055044P-2 340

744000 0.38744002 0.49 MEMORIES4412FP POA

4412VP POA45146 13.964515,2 p08 74116 3.10

74118 P0874LS154 1.2374LS155 0.38

74L0631 P08741_0639 POA

0.847460356 0.84

74607147 0.7074607151 0.52

74HC367WM 0.53741-10373WM 055

744004 azio744008 aao

7415 0.687418 0.72

ZENER DIODES3.0 WAIT

4, 49152, 2 10,12, 16 6 20MHz

T055174P-2 4.2070556501_-15 3.60DYNAMIC RAM

4416P POA4429PB POA

4515202 POA451550213.96

74119 POA74121 1.40

741_0156 0.3874L0157 0.42

741_8640 POA74LS640-1 2.79

7460365 0 527460366 0:62

74607153 0.5274607154 1.20

74HC374WM 0257460390M 057

744010 aao744011 aao

7824 0.7278L05 0.28

7.50 to 2700.

PeceI74'

Price: £3.66 ea.24,32,40,50966MHz 4164-10

P08

7M54014J0L 3.401=14433P P084443P POA4447P POA4467P1 7.204468P 6.944469P POA

44590 008

45156P213 96451570211 0845158P211.0845155 pa,45403P P0845406P 3.56454070 6.4774L0645

74123 0.8874125 0.6474126 0.9874128 1.4274132 0.8674145 1.1074150 1.86

74L0158 028741_0160 0.5274701604 0.6074LS161 0 4674LS161A 0.4974LS162 1.1074L01628 1.10

74L0641 POA74LS641-I 2.4774L0642 POA74LS642-1 POA741_0643 PO474LS644 POA

0.64

7460367 0.52ZENER7460368 0.567460373 0.487460374 a4874110375 0.787460377 0.527460386 0.38

74607157 0.4574607158 0.5074607160 0.5474607161 0.5474607162 0.8474607163 0.5474607164 0.52

7460393M 0537460540WM 0.7674HC541WM 0.7674HC573WM 1093.3V741-10574WM 0947460688WM 0.8474604017M 0.48

748C14 aao744020 aao744032 0.40748074 0.487440109 0.647440112 0.81748C138 ass

78L054 0.2878LI 2 0.28781_124 0.2878715 azs7BL24 0.2878L56 1.1078M05 0.70

p eachDIODES

5.0 WATTto 200V

Price:98p eachZENER DIODES

STUD MOUNT

Price £3.94 ea.

Elpin DILSealed Metal

PackageHCMOS Output

4164-12 POA4164-15 1.4041256-8 POA41256-10 POA41256-12 POA41264-15 2.2441964-12 445

ORO to 3M3

Case 1206 -Pack of 5Price: £0.30 per pk.

CAPACITORSSURFACE MOUNT

44907 4.504495P 6.554497P 6.984499P 6.98

454110 POA7470645-145414P P0845428 POA

74151 0.8074153 0.9074154 2 8074155 0.81

74L5163 0.4074LS1634 0.64741_0164 0.40741_0165 0.50

2.7974L5646 4.65741_5652 PO474L0669 1.58

7460390 0.487460393 0.417460423 0.547460521 POA

74607165 05274607166 0.5274607173 0.5274607174 052

74HC4020M 0.48741-104040M 0.4474604046M 1e8741-104060M 0A8

7440139 0.657440151 0.687440153 ass7440157 0.81

78M058 0.7078M12 0.7076M124 0.7078M134 1.40

20 WATT75V to 75V

Price: £7.40 ea'BRIDGE

13.2mm sq.Pins spaced atcorners of 8pinDILFreq.- MHz

41464-10 4.454464-10 2.804142564-70 POA44C2564Z-10 6.95

Multilayer Ceramic63 VOLT

Case Size: 1206L2XW1.25mm45008 15.80

4501UB 0.4445025 0.5645036 0.484504B 1.36

4000 SERIESSURFACEMOUNT

400107 0.32400207 0.32

74157 0.7474158 1.5774159 3.8974160 0.94

741_8166 0.5074LS168 POA74LSI 69 0.5074LS170 POA

7470670 0.7874L5673 POA7470674 16.8974LS682 2.62

o 0.947460534 0.967460540 0 69

'7460541 0.69

74607175 0.5274607181 3.240.94/200VD1774607182 1.20746C7190 0623.0A/200V

741104066W 094 7440150 0.657440163 0.607440169 1.987480174 0.65

78M15 0.7878505 1.1078012 1.1078015 1.10

RECTIFIERS

0.38SIL

3.6864,8,10,12MHzPrice: f4.13/3 each

162024,32,40850MHz

511000-85 8.45HM48416AP-15

4,,,,,

HM484166P-204.25

10p522pF,33pF,47oF10026,22066,3a:0F

4709F,1000p4.2200pt230066,471:404

746 SERIES

74600 0.2874802 0.2845055 POA 4011131 0.32

74161A 0.74 74LSI 73 0.52 74LS683 POA741_8684 3.85

7460563 0.88 74607191 0.59 7480175 0.60 7905 0513 0 57 Price: £3.84 each HY53C2561_5-80 10000:26.22000p645068 1.40 4011067 0.32

74163 1.2874184 1.16

74L81734 0.527470174 0.337414057374L5685 POA 7460564 0.880.68

74607192 1.20

74HCT19":5274604 028

7440191 1287440240 0.92

79054 0.98790584 0.68

6A/100V OH-1.60

---- ''''''' - '''''''TTL OutputPOA

HY530A641_8-130ascoopF

Price: 157 each450608 1.404508B 1.68

40126T 0.32401357 0.45

74165 1.5774166 1 06

74L0182 0.33741_18 POA

74LS686 POA741_8687 POA

741-105734 0.867460574 0.64

74607194 1.20741-107195 1.20

74606 0.7474607 0.74

7440241 0.927440244 0.92

7909 0.987912 0.68

84/200V OIL1.96

14pin DIL LayoutSealed Metal

POAW13511000-85 8.45 4700026 1000oopF45105 0.54 401567 0 84 74174 1.37 7475183 POA 741_5688 1.98 74607221 0.66 74608 0.28 7440245 1.10 7912A 0.98 4pin Package Price: 18p each

ELEKTOR ELECTRONICS APRIL 1995

Please mention ELEKTOR ELECTRONICS when contactin,t, advertisersMICROPROCESSOR

& SUPPORT ICs

100114DEC 7.40100141DC 9806303XP 8.766321P 4.4163485CP32/SM 19.9563603XP 1E076502 2766502A 3.986520P 4 406522 4.406522A 5.326551 4436551A 5.2065CO2P2 6.5465CO2P3 7.1665C102P2 6.7865022132 6.51650516.1 5.60650516-2 22068000CP-12 a6568000CP-8 67868000P-10 7416800013-16 18.206800813-8 6.856800P 5.706801013-12 POA6802P 3906803P 7986805E3E 14 75600913 4.98661 OP POA6821P 1 686840P 3226844P 17 206845P 4166845SP 4.8668409P 4 6068821P 1966884013 15668A5OP 2.9568BOOP 7.686860913 47368821P 2.5668B40P 3.2080805 POA808544-2 5988086 11.928086-2 11.92800286-8/PLCO24.4080032.16MHZ 8.9880C32P 4.2880085A 5.9180085A-2 18118-5CH

977.60

82054-2 4.1093L3400 7.08AM25LS2568P 2.68AM25LS2569P 2.68AM2602PC POA8M26L531DC 2.30AM26LS31PC 1.28AM270191ADC 10.20AM27S281PC 9.82AM2964B5C 12.36461296500 10.68AM2966P0 4.974M29826DC 5.98AM685DL 9.82AM8238PC 5.60AM905000C4m9050CPC8M9102CPC 2.82AM911413DM 9.96AM9551PC 9.66AM96L02PC 3.3587-5-8136 5.45AY -58136806 6.45C1164/SMD a08231801253 3.6004800856 5.980082085 9.620082086H-5 9.74CDP68186E 832COM8136 6.45COM131017 9.4101382054 6.42CRT1004-001 265CS8205 8.9203232 6.8608086 11.9208086-2 11.92082028 POA03254-2 142082848 390D82/380820234-12 9.600820284-8 7.850820288-10 10.960620288-12 11.850820288-8 9.36D8748H 10.26DP8228N 6.83DP823814 6.7201383040N 2.94DP8311N 8.51DS1221 8.11001231-20 550001232 4.12D0341361.1 1.74IDS3487N 1.7400340886 2940534087N 294DS363119 4.35DS3632N 3.4405363360536344 3.440536914 30400386211 1E9800500132-12 313080586400 1.715081320AN 1 920588324 388DS8836N 2.880508384 2.83DS8838N 2.750596368 1 980096378 1.680096385 118

DS9639A 198EF6821P 1.68EF6850P 1.68EF681309EP 5.35EF68809P 4.73DEB/1E121P 2.56EP610PC-35 POAH51-0165-5 10.96HD146818AP 441803-6402-9 216HD#03-6440-9 889H#03-6495.949620/BB6495.9 8.89H044183 POAHD46505SP POEHD46802P POAHD6321P 4.41FID63485PS32 32.50HD631303XP 11.74HD68000P6 11.59H5680313 7.98H068455P 4.86H06845213 POAHD681321P 3.53HI1 7159-5 20.68#13-71596-5AD585A023.40HM10422 14.2008208614 17.06M6402AIPL 10.20M64021 PL 7.75M6403I PL 12.92MS2600P-15NS8250N 7 80NS8250N-B 7E0M5M82C5IAP 5.89M5M82054P46 657MA1380314H12P 4.23MABI1035HLEP 5.98MCI 0103P 2.89M010115L 3.85

C-1M0115P 2.89MC146805E2P 6.53MC68000P12 POAMC68000P16 18.20MC68010P10 POEMC68010P12 POAMC6802P 3.95MC6821P 1.99MC6840P 5.05MC6844P 18.40MC6845P 7.38MC6850P 3.35MC68705R3P 25.3561068800P 7.02MC68A09P 7.62MC68HC05E0F511.96MC8314P 160MCM681 OP 498MCM68410P 742MM53200N 4.73MM58167BN 13.65MM581749N 14.82MM582740N 9.59MSM5832R 5 5MSMBOC35RS 4.90MSM80039/SMD 645MSM80C39RS 7.55MSM80C85A 5.91M554200254-2 5.98MSM130C88 710MSM81055 4.60MSM82C51A 4.87MSMB2c53-2 538MSM82C53-5 5.38MSM82C54-2 4.20M5M82055A29S 5.18m521820594-2 3.98MSM82034A 4.42MSM82C134A-2 495MSM82C88 12.60N80028110/PL 24.506800286.12/PL 29 54N80L286-8C2 3620

3.68562845N835N1.202 3.68

N820126AN 5.881I825181F 10.04NS16450N 5.98NS1655DAFN 12.60N008001913803288 4.621380514H 11.20P80524H/BASIC24.99P8080A POA

5.92P80854-28.75P8085AH-2 6.88P8088 6.80P80031613 .26P80032/INTEL 8.30P8C/C51FA 16.52P800136AL-2 12.60P8155H/2 6.98138205 2.00P8212 2.40P8226 2.40P8251A 4.05P8253 4.701382558.5 3.90P8259 2.85P82596 415P8274 16.71138279-5 3.20P8282 2.64P8286 3.60P82C54-2 8.98PAL10U3CN 1.90pAL12H6CN 1.90PAL16R4-150/9 2.98PALI 6R4BCN 2.17PAL20L10CNS 4.35PAL200,30810 3.32P008584P 12.22130085847 12.22PCF85613P 8.28P0F85667 8.28PCF8570P 8.63P088573P 9.64P088574P 7.68130885747 7.68PCF/3591P 12.26P1016C54RC/P 3.601401605580/P 4.48PIC16C56RC/13 442

PIC16C57RC/P 5.06PIC16C64-04/P 13.98PIC16C64-20P 23.85PIC16C64-JW 3096PIC16C71-11P 8.94Pi016084-10/P 12.24PIC17C42-16JW 35 51R6502AP 191136520P 440UNEAR86522 4.4086522813 1865002P2 8.54065CO2P3 7.16R65CO2P4 8.9513650102P2 6.78065021P2 5.46R65022P2 6.51s41380032-16 6.98sAi380C32P 4.28588800535-N 12.24SAB8151P 3E258682598P 3.59SAB82C54-2-P 4.12SABB2C55A-2-P 4.800080C451CCN84

13.600087C51CCF40 31.50SC87C510C340 31'255052661001628 POACM72171J1SCN2661CCN28 POATLi 6C550AN 13 96TMP7002NL-2 4.97TMIPB085AP-2 198TMS320C1ONL 9.327MS320C25FNL 17.23TMS320C25GBL 70.58TMS3477NL 168TMS3700NSB 5.78TMS3702ANS 9 78TMS3835AN5 7.55721577031NL 10 74TMS9900NL 2440'TMS9901 NL 14.1672109902ANL 15.94TMS9914AHL 2a10TMS9928ANL 7.40TMS9995JDL 69.85U496364CP 2166UA9637A 2.38049638CP 2.66089639CP 2.380M68456 4.95um9151 POALIM9151-3 POAuP88238 POA0P682820 4.98UP88284AD 4.98UPB82860UPD70108C-10 9.10upD70108C-8 6.95L:070116010 12.90upD70116C-8 9.20UP571055C 4.77up072014C 6.93UP57201C 6.12UPD7654C 5.42upD780C-1 9.76up080C351HC 8.42UPD8155HD 5.84upD8251AFC 4.08UPD8253C-2 3.98UPD8253C-5 3.98UPD8286C POAUPD8741AD 12.52UP08749HC 14.7402110MHZ 9.10V20-8MHZ 6.95V30-10MHZ 12.900328MHZ 9 .20761030P 7.80VC0106763x68H005E0FN 11.86Z0800110P50 16.90Z0868112PSC 3.202180-81PU POAZ8001 / CPU 11.96z8018006VSC 2252808 -CPU 2

Z80A-CTC 2.98z804 -DART 4.947808 -DMA 5.407804810 2.60Z818510/0 9.762808 -CPU 2.60280E-CPU/CMOS 4.66z806-0TC 3.0278013 -DART 4.932865_DMA POA280B -P10 3.007802010/0 9.92Z800004138 3.38284042 CMOS 160Z8681-81 179

SGS7P050 4.55SP1450B 176ULA1R1302961 6.80ULA2ORK008615 972XR-T5683 3.60ZNA2L029J-BS 280ZNPCM1J-BS 195

CL7652BCPD 8.24CL7652CP0 8.24CL7660CPA 188CL7660SCPA 2.96CL7662CPA 335CL7663BCJA 178CL7663BCPA 110CL7664CPA 795CL7665ACPA 4.47CL7673CPA 1.26CL8052ACPD 173CL8068AJD 1149

4.09CL8069DCSO 2.83CL80690CZR 2.21CL821 1CPA 1.49CL8212CPA 274CM71701PG 114CM7207AIPD 1135CM7207IPD 794CM72091PA 6.99CM7211AMIPL 5.25CM7211MIPL 6.75CM7212AMIPL 112CM72131P0 9.11CM7216AI21 30.890M721741P1 842CM721 7BIJI 1298

15.269.30

CM721841PI 8.68CM7218DIJI 1095CM7218EUL 1476CM72241PL 142CM7226AIJL 37.20CM7226BIPL 3252CM7249IDM POACM7555IBA 0.99CM75551PA 068

1.16M6403/PL 12.92L272 274L272M 2.38L293B 312L2535 3.27L.297/1 1981298N 780L4805CV 3.40L487 3.76L4960 2.79

3.68POA

LA6510 4.88LA6520 6.22LC7132 PO4L07522 197L,7555 9.78L5111401 POALF13508D 1165

6.87LF347N 1.34

0.48LF353N 0.61LF355N 126

1.33LF357BN 2.98LF357M 2.40LF357N 1.33LF398N 3.77LF411CN 1.22LF412CN 1.69LF441CN 012LF4420N 1.48LF444CN 1.98LH0002CN 13.04LH003200 35.96LM101511 344LM100N 724LM111H 5.21LMI 36004 1.89LM13700N 1 58Lmi 391N 1.98LM139J 3/5LM14585 059LM1496N 2.26LM18015 712LM1881N 4.48LM1889N POA

i4(4215,4 POALM2396 390LM2901N 0.86LM2903N 0.86LM2904N 0.86LM2917N-14 610LM29175-8 384LM29400715 POALM2940075 POALM2984CT 496LM301 AN 154L,807, 0.961.618084 0.91LM3105 256LM3115 0.38LM311N-14 2.15LM3I 2H 8.95LM317AT 2.40LM3177 176Lm317T-L7 284LM3185 3.12LM319N 2.68LM32OLZ-12 034LM324AN 374LM324J 171LM324N 138LM325N 609LM3301N 210"554z 171LM335Z 1.62LM336Z-2.5 1.48LM3362-5.0 1 48Lm3574. 1.12LM339AN 2.37LM339N 0.34LM340AT12 2.05LM3407-5 0.70

0.70LM340T15 0.70Lm345,4 9.22L61346N 4.12LM348DP 0.64LM348N 0.64

LM350T 4.77LM351N 2.60LM358N 0.36LM359N 2.84LM360H 7.72LM36IM 140LM363H-100 16.50LM369DN 3.82LM369DRC 170LM380N 198LM381 AN 718LM385Z-1.2 198LM385Z-2.5 1.98LM386M1 115LM386N1 1.28LM386N3 1.80LM386N4 2.60LM387AN 5.20LM38851 4.25LM389N POALM3900N 1.02LM3909N 2 12LM39141,1 125LM393N 0.56LM393P 0.96LM394CN 4.80LM3999Z a21LM399H 6.68LM4250J 11.82LM555CN a68LM560C4 248LM710CH 1.71LM723CH 1.63LM723CN 0.72LM733CN 2.65LM7410J-14 2.20LM741CN 0.45LM747CH 240LM747CN 074LM78G0P 1.80LM79GCP 1.80LM833N 1.31LS285AB 2.40LS288B 4.32LS7210 POALT1006CNB 2.72LT1010CT 4.58LT1028CN8 7.98LT10320N 4.70LT107007 10.98LT1083CP 8.82LT1088CT 3.81LT1134CN 8.14LTC1052 7.97LT01099CN 14.39LTC485CN8 2.60LTC490 4.40M5218AL 3.20M5220 6.21M5238L 3.98M5298P 6.22M706111 1/2MAX134CPL 17.95MAXI 232CNG POAMAX1232CPA 2.42MAX1259CPE POABIAX162A0NG POAMAX2324CPE 212MAX232CPE 2.54MAX232EWE 180MAX232N 4.98MAX280CPA 6.94MAX452CPA 138MAx627C134 3.40MAX6600PA 6.30M4069040P8 466MAX693CPE 6.68MAX694CPA 1 70MAX697CPE 1MAX7219050 788M508211CPA 228MAX9018CPE POAMC1377P 4.936101413P 0.74MC14411P 1425M014416L POAM014495P 698MC145406P 2.80

MC1455P1 1.40MC145819 0.60mc1488L 240MCI 488P 1421001489AL 225MC1489AN aBoMC14891. 2.20M01489P 0.38M01496N 17661015661. 332MC1648P 12.40MC165817 12786101709cp1 1.20MC17230P 1 20MC1741CP 145MC3242AP 7.542AMC3301P 2.60MC3302P 2.46MC3340P 375MC3357P 3.98MC3403P 140MC3446AP 6.75MC3479P 7.92M03523U 180MC4024P 12.78M012 0.98M0761 1.18MF100,CN POAML924 4.90MM5309N 5.7661115310511 4.98MM80095N 1.44MP7570JD POAMUX2460 14.82MUX24FP 14.82MV5000P 2.86MV6012P 496MV8870DP 796NE5020N 11 685652711 4.636E5324 1.81NE536H 8906E55305 312

NE5532AN 2.02NE5532N 0.82NE5534AN 1.28NE555N 140NE556/SMD 122NE556N 1.18NE5585 2NE564N 3.75NE565N 2.94NE567N 0.91NE56BN POANE570N 7.53NE571 N 4.96NE589N 4.25NE592/SMD 1.80NE592N 210NE592N14 200NE602AN 298NE604AN 198NE605N 11.85NE612AN 3.40NJ8821 DP 12.06OP07CJ 3.60OP070N8 1.400P070P3 1.40OP97E13 110OPI IGP 6.68OP177FP 17101327013 41]OP42FZ 9230P770P 3.23OPO7CN 192-.APCM63P K 35 80PM7548HP 17.99804136N 0.8080428042070/9 1.92804558 19180455813 0.91REFO1 CP 3.48REF21HP 7.40REFO2CP 4.95REF03GP 5.42REF25Z 0.98S2560A POA5881027 5.94SAA1043P 9.60SAA3049P 1198SAA5025D 94054460024 10.80SAS5605 140SED2000FVA 9.605802301450 1780802741 DC a305035246 1.6651766004 1.92SLI 452 7.85SL2369C 197SL31176 POASL4B6DP 2.82SL4900P 260SL560CDP 300SL6270CDP 2.97SL67000DP POASN5281CN POA555545111G 2.8500012 a22sp16431)0 6.60S134534 POA5P47400P 4.46SP86600P 4.96STK4I 4111 5.20STK5151 6.40578417111 7.10STK4181-V 910018419211 7.80STK4277SL 10.80TA7215P 7.20TA7256P 2.6078736813 PO474765813 1.2078780058P 0.48748200AH 7.82T88410K 2.80TA8449P 131T886596N 12220448614 P08zN425E8TBA1205 am

TCM1531P POATCM1705AN p04TCM3105N 9.42TCM5087N 3.44TCM50B9N 3.447081023 2.307081083 3407081085A 3.8075410850 3.802112369A7081151 1.88TDA1170,5 3.54TDA1515A 4.9870815218 4.887081576 4.9870815788 4.811052096/A POATDA2595 4.417083048N 1857083505 POATDA3810 p08TDA440 POA7084510 3.387084583 4.98704466070A6579T POAT087010T7087052 2.521548702 6.22TEA1045 POATEA1060 4.201E85620 POAT1PC280114V 8.79TL026CP 1.84TL062CN 1.26TL062CP 1.30TL06400 0.98TL06406 0.84TL0641D/SMD 2.10TL0714CP 1.57TL071CP 0.78TL07240P 1.64TL0720N 172TL0720P 1/0

71_074ACN 240TL0740N 0.97TL081CP 0.74TL082CN 0.81TL0840N 0.84TLC27L2CD 1.96TL497ACN 3.95TL507CP 5.96TL7702ACP 1.22TL77054CP 1.22TL7705CP 1.22TL7709ACP 2.04TL7770-SC 3.82TL783CKC 753TLC15411N 15.63TLC2201CP 5.50TLC2274CN POATLC251CP 428TLC26520P 5.98TLC2654CP 5.98TLC271CP 1.20TLC272CP 2.16TL0272CD 2.29TLC274CN 3.09TLC339CN 2.58TLC372CP 1.95TLC551CP 4.62TLC555CP 1.44TLC556CN 2.53TLC7524CN 5.98TLE2061 CP POATLE2062CP POATLE2064CN POTLE2161CP POATMS3477NL 1687131024066E 7.14TPIC2802KV 9.42TPIC6259N 3.28TP1062735 328TPIC6595N 3.28TSC426CPA POA750500013E POATSC7106CPL 181TSC7116CPL 7.68TSC7126CPL 8.28TS07660CPA 1.40U10968 4.02

020668 214024009 5.50042240CN 2.79042240PC 279UA709CP 01504709130 0.8504715HC 4.5008723013 0.7004733CJ 296UA741MP 0603874170 028U4748CP 0.98U477000UIC POAU4798TC 180UCN5800A 2.83UC55801A 3.96UDN2981A 3.15UDN2982A 3.02UDN61184 2.13UGN3501M POAULN2001AN 0.58ULN2002A 0.58ULN2003AN 0.58ULN2004AN 0.58ULN2024A POAULN2032A POAULN2801AN 184ULN2803AN 284UM5100 POAUM5101 4.52

XR2211CP POAVN66AFDXTR110KP 11.847111211 4.607M362313 15.48ZN1034E 2.66ZN414Z6ZN415E POA75416E 2.32ZN423 2.28

4.95zN426E8 5.35

ZN42868 6.40zN429E8 1.98ZN432E 21.49ZN4486 7.95ZN449E2N2219AZNA134E 16 727N8134H 12.73ZNA234E POA

75176A 2E9751766 1.867517637 11975177 16075178 4.1475182 29375183 2.9375188 0.9675189 0.9875189A 0.9875361 3.7475365 15075437A 3.267545213 0.6675451 166754518 0 9675452 166754520 0.9675453 01175453B 29675454 0.6475454B 0.9875462 1.3175463 1.1075468 3.1575469 130475470 80875471 3.3575472 13575473 33575474 22575477 2.1075491 0.9975499 3.9875ALS176 4.2475ALS192 4.7275ALS193J 4.72135X217501154 4.067501408 251750185 19875018/3 2.327501896 2.3275C189AD 2.3275LBC176 4.14

BD743C 1.90BDT85 1 12BDX676 218

-44,80796.,BF195-C 008BF199 122BF200 0.16BF256B 0.38BF256C 0.38BF259 0.40BF324 0.286E421 01256450 0.20BF451 0 22138494 11688759 0.268E961 "EBF981 090BF982 188BFG6S 1.7913E1153-22Hz 0.48BFF191-5Ghlz 0.90BER91A-8GHt 1.20BFW10 1.20

BFX48 049BF085 159BFX813 030BFX89 1 5913E1(50 0-348E1152 0.39BF790 0.92B0107 0.26430170 2388S250 01285860 0.48BSX20 018

3.46BSX61 11557138.800 1.18BUW46 494Buz) 1 1.606UZ118 1.62BUZ47A 6.90IFIFZ14 1.14

IRFZ20 1.77J113 0.39

75 0183270 0/2JA101 0.48MEID501 1.10

MJE13070 1.10MJE340 0.68MJE350 1.10

0.800.18

Mps406 0.12MPSA13 0 12MPSA63 012MPS/02 024MPSU05 221MTP8P08 2.10MTP6P10 2.80FN3643 0.16TICI 06M 0.78TICP206D 0.617101/1013D 124TIP115 01571812., 0.66TIPI 45 1.37TIP2955 0.88

2.42TIP3055 0.88TIP31A 0187113328 140711347 180V275LA10 0.92

0.92/.40

VN90AB a96Vp0-104-N3 0.927130104N2 0.98VP0104N3 0.92770212 0.1821X237 0.2677(300 0.1627103131. 0.287110.320 0.38

03 8X5100.08ZT0550 024ZTX551 0.36

Personal Computer Products

MOTHER BOARDVESA 986 3VLslots,256kCache f85with ZIFF Socket for CPU and8132 & 2x72Pin SIMM Socketsaccepts 486SX/DX/DX2-66 CPU62(without CPU&DRAM)

MICROPROCESSORS80486SX-33MHz INTEL E 758048600-33MHz INTEL £ 1251304860X2-66MHz INTEL £ 160Heat Sink 1- Fan for 486CPU £ 10

HARD DISK DRIVES270M8 1361sec 3.51 LP £149340MB 1331sec 3.5" LP £ 179FLOPPY DISK DRIVES1.44MB 15" £ 28

5.25" £ 38

GRAPHIC CARDSISA TRIDENT TVGA 8900D 1M6£ 48ISA TRIDENT TVGA 9000 512413 £ 28VL Bus Graphic Card 1MB £ 55expandable to 2Mega Bytes

MEMORIES (SIMM)1Mx9x3 CHIP 70.0 E 30

(4MB 72PIN) 70ns POA256Kx9 3 CHIP 80os £ 12

I/O CARDS with CablesIDE 2H0/2FD/20/1P/10 £ 15VL/B Mold 1.0.Card £ 25

KEYBOARDS & MICE102 UK Enhanced KeyBoard £ 17102 UK High Quality Keyboard t 25Keyboard3 Button Serial Mouse £ 8

IMPORTANTAil prices are excluding V.A.T.

Postage &Packing ChargesC100 for orders upto £40005. V.A T.

and55.00 for orders over £40 exc.V.A.T.

applicable to all goods under theheading of

'Personal Computer Products'.

Postage & Packing will be charged atcost for all destinations outside the U.K.VA T. 4 payable on Peseta, & PacXng.

& MISCS.

363011M/BB 14032POA

555 -TIMER 0.40CL8069CCSO6

0PAMP-1J341 PA

741- 0.18O

AD520JN POAAD524 21'02AD534JH 4827AD537JH POA

2.06AD548,1111.2MBAD574AKD 54.57AD578JN P0AoAD581JH -72AD581KCSA 9.97

--315571994-5

AD5920N POAAD594AD 18.80AD595AD 15.24406483161104363.09AD707JN 3.65CM7218AIJIAD711JN 2'61AD712JN 3M7AD7245JN/KN POAAD736JN 821AD741KN487,2366 93Irn- 4.AD7537JN 38.04AD7537LN POA40754201 3935AD7543JCWE P08CM7556IPD40757866 5081AD844AN 171ADC0804LCN 3.98ADC804LCWM 1110ADC0820CC5 1993ADC0834CCN 1010A208460-10 38.98ADC9013HP 18.42AD0A080N POAADG201AKN 7.59

9280013070N 1.L702438H001500 17.20LA6351AT1.1270 3.6047-5-1013 4.60A7 -11013A 5.98IEZEZEMEEI47-5-1250 POAAY -5 -3800 -PRO 996BA6109

1-680A6228 1-40083046 0.54LF311HCA3046(SMD) 0.89

68093054 1.LF351N083059 11011CA3078AT 3.84

20083079 1.LF356N0830806 2'60CA 3081 414C83089E 1.680430944E 2160430966 3'64CA3097E 2M2CA3120E POA08313013T 19.20043130E "1CA3140AE 1.60043140E 242083146E 0.980831606 149083240E 427CA224°1 3M90432600 "4083280AE 5.94043280E 3.42c4555CE 0.40087410E 0.18

005503- KG POA0X79258 POAD16903 POA.79DACOBOOLCN 140DAC0832LCN 5.600AC08C13 3.53DACO8EP 4.65DAC1008LCN 10.73DAC1222LCN 20.40DF1700P 17.91DG201ABK 183OG211CJ

1-26DG508ACJ 3.47DG508CJ '''250514880 "25514C88M/SMD1.655014086N 1.47DS -140894N 1.47HA12017 1 55H813426 11.

'

HAI 7723 1.40H075189P 0.80HEF4754V POAH11 -0201-5 143F111 -506A-5 11.21HI1149-5 POAH11 -5744K13-5 42.50HI3-0201-5 3.95

HIO 00096-5 FDAHI ILI 2.40H0574 -AK 1120

L7104-16CPL26.08CL7106CPL 160

L7107COH 120L7109CPL 1194

CL7118CPL 8.53L7117CpL 11.02L7126CPL 11 02L7135CPI 12.19L7136CPL 11.02

CL7137CPL 1112L76060,JN 1224LM340712

CL7611DCPA 1.41CL7621DCPA 1.98CL7622 POAL76500PD 5.68257897L7650SCPD 515250945

TRANSISTORSTHYRISTORS

& TRIACS

40406 1E040673 290130107A/13 0.17130108A/131C 117001096/0 0.1860140-19 0.48

158130146/01BCe49 '"60107 23480154 0-34BC169C 11480179 12480182 0.08BCI 82A 0.08001820 208BC1821. 0.08

80182L0 5-28BC183 0.08BC183C 0.08B01831_ 0.08BC184 0.08B04 84B 0.0800184L 0.08BC184LC 808BC212-18 0.08130212A 0.06

08602126 0.7/90104/9350212LBC2i2L8 0.086980213BC213I- 8BC214 riaBC214L 0.11

60237 ''''62239 0.1250307 0.0880327 0.0880328 0.088033780837.25 "'4BC489 0.2400490 0''''"00516 0.2280517 0.2050546 aM5

0.05BC'4°A805460 M's'"80041 0.08BC5474 0.BC547BBC547C am00548 0.013BC54913 a60549 0.08B05496 0.00,5052550 .--BC550C 0.081305513 0.0860556ABC50613 0.08

BC557 0.08EIC55713 0.08BC558 0.08B05584 0.08505588 0.08BC559A 0.08B055913 0.08BCS6OA 0.08BC560C 0.08BC184C 0.088C771 0.22BD131BD135 0.44BD241A 0.98602420 0.5280243 0.50130518 0.7850675 0.5250676 0.5280679 9-5480680 0.56

A to D Converter with Software596 each

ask for leaflet for full details2 Digit Display Board for Turbo PC

Diplays 1 to 99, Jumper selectableCan he wired e.g. 25MHz & 66MHz

46x56rnrn £15.95 each8 Digit 7 Beg. LED MPX Display

Board fitted with 2x8Pin SIL Headersize 15X61 mm, supplied with HP

HDSP-7511 0.3" (7 6rnrn) Dis plays.use Common Anode Display DriversCP172168/0 or 10M7218A/CrEIJLetc.

Kit: 518ea. Assembled: 524 ea.Vaccurn Fluorescent Displays

CU205ECPB 20 Digit 507 Dot Matrixby ISE Japan, 176056mm C32 eachAll Sial Products: P&P £1.20pec

2N4401 1182N4403 0.18254921 1.40265401 0.18255415 0.72255449 0.88255459 0.532N5485 0.48255876 1.322116034 0.72256037 0.722N6050 3.122N6051 3.49266054 2.20256056 1.942N6057 2.242N6058 2.682N6109 0.78286125 2.08256388 0.98206517 0.34256519 0.34256668 1.4026696 0.26207066 0.482SK129A .220K296930845 18530888 0.84

20E11052 1.202501185 1.5220131238 18220137504 120208834 114250949 1.98206950 1.402001079 5.802001115 4002001129 0482001213 0402501279 1.102501318 0.6025017405 0.4025017416 1322501775 1282501845 1282002009 0.4425021805 1962S02235 0402502238/0 176250223813 0.762002240 0.242002275 0.6425022756 0882002278 1.182002362 0.342002389 a362002497 1.20

TRANSISTORSTHYRISTORS

& TRIACS028

2N2222 0.282N2222A a22252369 0.24

0.242112484 0.322N2894 0.78252905 0.32252905A 0.32252907 0 302529074 030252923 1302N2243 078253053 0.34253055 0.98253441 1.25

253553 0.982N3684 1.65

2N3702 0.10253704 0.10253706 0.10253725 0.78

2N3789 2.162N3819 0.54253866 1.24253904 0.11

0.12253906 0.102N3958 2.12254037 0.4825405 2.30

254062 0.322N4091 0.75

254123 0.102N4124 0.20200826254125 0.18254126 0,32

2N4221A 2962N4236 372

75 SERIES

75107 1.66

751078 46675108 1.4275108A 1.84

75108B 2.0875109A 2.46751108 2.4375113 2.0275114 2.26

75115 2.25

75116 5.74

75121 2.5975122 paa75136 FDA

75138 5.74

75140 13575150 1.3975150M 1.3g

75152 5.35

75154 1.33

75154M 1.3975155 3 06

75157 44075159 5.45

75160A 6.15

751618 6.1575162A 6.15

75172 2.46

75173 24675174 247517450 4.2175175 220

JAPANESE

TRANSISTORS

2502577 1/42002579 3202002591 1/8

TELECOM & SPECIALFUNCTION1Cs

20510487 2142081096R 0.962051100 0.602081102 °25411042581111 02581115 02541145 0.452051263N 1.802SAI 264N 2.602041265N 2.602081283 0.282041295 7.322041302 3.742041399 .582041482 .782041515 0.782041518 3.24208733 0.302088540 0.52258933 0.242049330 0.392SA965 0.60205968 1.10258970 0.32

2SC2603 8322002705 0.442002928 4.822503180N 2.382003101N 2202SC3182N a642003243 8362503281 2722503284 5002503377 0242003581 156200369 0.44250373 2442003907 4.20200458 0 15200465 118200486 1.88250497 1.642505386 1.98200627 0.68200815 168

0.82200853 0.82

180120

200971 0.88

6200/390 4118 3.70707W02020 5.25733W00124 5.25AMAI5030X13 4.680881505/Ple09e0 2.20CLA25106/PLCC 5.95GA05001000 3.2088960013 11.72KS-49258/PLCC 5.92MJ1459BB 7.65MK5175N 3.8000-147-7 2.40P00352303 840PP34C10804704 3.80OMV1613P5 7.98OMV18C 5.05

aMV-18CN1 7.850M1/180W1 7 85ONIV25C 842OMV62AW1 6.9054534-4M1 82058336931 3.2000M66115P 498

Important Notice - Our Telephone & Fax dialling code changes on 16 April 1995 - from 081 to 0181 - you can use either up to 15 April 1995

VIEWCOM ELECTRONICS PLEASE ADD £1.20 P & P and then 17.5% VAT. OFFICIAL ORDERS from Govt. & Educational Establish-ments are accepted. VAT at 17.5% is chargeable to all orders received from EC Member Countries unless77 UPPERTON ROAD WEST VAT Number is quoted. OVERSEAS orders, postage AIR/SURFACE will be charged at cost. VAT is not

PLAISTOW, LONDON El 3 9LT applicable for EXPORT orders from Non -EC Member Countries. Stock items by return of post.N.B. All prices are subject to change without notice & stock availability.

PLEASE PHONE/WRITE FOR ITEMS NOT LISTED Retail Shop: 139, New City Road, Plaistow, London E13 9PXELEKTOR ELECTRONICS APRIL 1995

14

41

CHIP CARDS

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Based on an article by J. Heine

CHIP cards with a variety of appear-ances and functions have beenaround since the middle of the nineteenseventies. Today, they are used increas-ingly in, for instance, telephone booths(though not yet in the UK) and personnelidentification and work time logging sys-tems in large plants and office buildings.In some cases, they are also used for elec-tronic financial transactions. In the nearfuture, further measures towards appli-cation -independent, international, stan-dardization of the chip card is sure togive a tremendous boost to the number ofapplications. This will be helped by muchreduced productions cost, which goeshand in hand with high production vol-umes. Also, a combined chipcard/magnetstrip card will soon be unveiled.

The primary function of a chip card isto help identify the rightful owner, or,with non -personalized cards, to grant theuser a certain service for which a remu-

neration is due that is within the limitsof the 'value' of the card. In this respect,chip cards are the successors of the wide-spread 'flexible friend', the magnet stripcard issued by banks and credit card or-ganizations. The requirements as re-gards physical and electricalcharacteristics of the chip card are laiddown in ISO standard 7816, part 3.

Construction of a chipcardThe generic name `chip card' is used tocover the following products:

- Smart Card- Memory Card- Processor Card- Intelligent Card- IC cardThese different names already hint atdifferences as regards function and inter-

nal construction. According to theISO 7816 standard, the name `IC Card'should be used to denote all members ofthe chip card family.

Magnet strip cards with their passivefunction and small memory capacity(342 bytes) are easily read, copied andforged. By contrast, chip cards, by virtueof their much larger memory capacity (upto 32 KByte), built-in intelligence and ac-cess lock, offer a much higher degree ofsafety against unauthorized use. Yet,they are relatively cheap to produce.

ProductionThe chip card has the same size as abank or credit card: 85.6x54x0.76 mm.For mobile telephones and other applica-tions where space is restricted, so-called`Plug-in SIM®' cards are available with asize of 18x28x0.76 mm. The chip properhas a size of 10x10 mm2, and is embed-ded in plastic carrier material. Becauseof the flexibility of the card and other ex-ternal factors, the carrier 'floats' inside aclearance in the plastic carrier. The chipcarrier element is produced by coveringboth sides of a foil with copper foil. Next,the contacts and the layout are etched(Fig. 1), and subsequently through -con-tacted. Onto this composite foil, anequalizing foil is laminated, from whichthe clearances for the chip contacts arepunched. The chip is secured on to theequalizing foil with the aid of silicon rub-ber cement, connected to the conductingfoil, and subsequently covered by an-other foil. The rear side of the conductingfoil contains the contacts (shown in theform of a punch -out pin feed strip in thebackground of Fig. 1), which later formthe contacts to the outside world. A fur-ther layer of foil, which has clearances ofthe size of the contact elements, is se-cured at the contact element side of theconducting foil. The finished carrier ele-ment is punched out of a larger sheet,and inserted into the card, which con-sists of several layers of PVC foil. Thesemake the card resistant against hightemperatures, high humidity, and chemi-cals. However, direct heat transfer to thecard, as well as electrical noise at thechip contacts (ESD) and excessive straincaused by bending, should be avoided.

Block diagramThe basic elements in a chip card areshown in Fig. 2. They include:

- a microcontroller (CPU)- a scratch memory (RAM)- a program memory (ROM)- a data memory (EPROM or EEPROM)- an input/output block (I/O)

Depending on the application, memorycards may be preferred over processorcards. In the long term, however, thetrend will be towards combination cards

ELEKTOR ELECTRONICS APRIL 1995

CHIP CARDS Elrit

Fig. 1. Building blocks of a chip card: infront, the etched chip carrier element, in thecentre, the (unfinished) card, and in thebackground, the punching tape.

and standardized readers which acceptall types of card. Two of the world's majorcredit card organizations, VISA andEurocard, already supply combinationcards which allow users to make creditcard purchases in the usual way usingthe magnetic strip system, as well asmake telephone calls with automaticpayment via their account. In response tothis trend, telephone booths in manycountries are rapidly upgraded to acceptthese cards.

Because of the standardized protocolas regards access, and because their 'in-telligence' allows them to be tailored tofuture protocols, processor -type chipcards are generally considered the bestcandidates to pioneer a universally us-able and global chip card technology.

AccessThe card has six to eight gold-plated con-tacts with an effective contact area of

Fig. 2. The basic architecture of a chip cardis fully equivalent to that of a microcontrollersystem.

1.7x2 mm2. The two p