the memory elements. words in high-speed memory read-write random-access memory
TRANSCRIPT
THE MEMORY ELEMENTS
Words in high-speed memory
Read-write random-access memory
The Memory Units•1 b – 1 bit•1 Kb = 1024 (210) b – 1 kilobit•1 Mb = 1024 (210) Kb = 1048576 (220) b – 1 megabit •1 Gb = 1024 (210) Mb = 1073741824 (230) b – 1 gigabit•1 Tb = 1024 (210) Gb = 1099511627776 (240) b – 1 terabit
•1 byte = one 8 bit word (a sequence of 8 bits at the same address)
•1 B – 1 byte•1 KB = 1024 (210) bytes – 1 kilobyte•1 MB = 1024 (210) KB = 1048576 (220) B – 1 megabyte•1 GB = 1024 (210) MB = 1073741824 (230) B – 1 gigabyte•1 TB = 1024 (210) GB = 1099511627776 (240) B – 1 terabyte
Basic static memory cell
Linear-select
SRAM
Decoders
Decoders condt
Decoders condt
Two-dimensional static memory
cell
Two-dimensional memory
organization
Two-dimensional memory
organization condt
Comparison of numbers of electronic elements used in one-dimensional and two-dimensional systems of memory
Number of memory cells
Linear selectionTwo-
dimensional selection
16 64 transistors 16 transistors
4096 49152 transistors 768 transistors
1 megabit (220)20 000 000
transistors
20 000 transistors
Bus for computer
system
IC package of RAM chip
Interfacing chips to a bus
Layout for adding memory to a bus
Another IC package of RAM chip
Dynamic random-access memories
DRAM timing signals
in normal and paging
mode operation
Read-only memories
Read-only memories
condt
Types of read-only memories
MROM (Eng. Mascable ROM)
PROM (Eng. Programmable ROM)
EPROM (Eng. Erasable and programmable ROM)
EEPROM (Eng. Electrically erasable and programmable ROM)
An important application of EEPROM: Flash-BIOS