land pattern design calculator for leaded components
TRANSCRIPT
Fig 1 - PSOP44
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DIMENSIONAL ANALYSIS OF PWB/COMPONENT GEOMETRYCUSTOMER: PRODUCT:
DEVICE GEOMETRY - PSOP44
0.53 mm 0.53 mm ("T") . ("T")
16.0 mm("L")
14.8 mm("S")
PWB LAND PATTERN DESIGN (PWB GEOMETRY)
PWB Pad PWB Pad
2.550 mm 12.000 mm 2.550 mm("Y") ('G') ("Y")
17.1 mm('Z')
RESULTS OF ANALYSIS
TOE TO TOE DIST = 17.100mm
TOE FILLET = 0.550mm or 22.00 mils
HEEL FILLET = 1.400mm or 56.00 milsAcceptable Minimum Toe Fillets: 0.254 mm or 10 mils
PSOP 44
Fig 1 - PSOP44
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THE FOLLOWING IS THE OPTIMUM PWB LAND PATTERN DESIGN:
Y = 2.55 MM
G = 12.00 MM Z = 17.10 MM
Y = 2.55 MM
LAND PATTERN DESIGN CALCULATION FROM THE DIMENSIONS GIVEN IN IPC-SM-782A SPECIFICATION
COMPONENT DIMENSIONS LAND PATTERN DIMENSIONS TOE AND HEEL FILLETSL Min L Max S Min S Max T Min Tmax Z G Y Toe Max Toe Min Heel Min
15.24 mm 16.51 mm 13.24 mm 14.63 mm 0.60 mm 1.00 mm 17.10 mm 12.00 mm 2.55 mm 0.93 mm 0.29 mm 0.62 mm
LAND PATTERN DESIGN FROM GIVEN NOMINAL PACKAGE DIMENSIONSCalculation of PWB Dimensions (Z, G and Y) with Desirable Heel and Toe Fillets
L NOMINAL S NOMINAL T NOMINAL Z G Y TOE NOMINAL HEEL NOMINAL16.00 mm 14.80 mm 0.53 mm 17.10 mm 12.00 mm 2.55 mm 0.55 mm 1.40 mm
Calculation of Heel and Toe Fillet with the known PWB Dimensions (Z, G and Y)
1.27 mm or
0.050"
0.6 mm or
0.0236"
0.67 mm or
0.0264"
Fig 1 - PSOP44
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LAND PATTERN DESIGN CALCULATION FROM THE DIMENSIONS GIVEN IN IPC-SM-782A SPECIFICATION
TOE AND HEEL FILLETSHeel Max
1.32 mm
LAND PATTERN DESIGN FROM GIVEN NOMINAL PACKAGE DIMENSIONS
HEEL NOMINAL1.40 mm
Fig 2 - TSSOP24
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DIMENSIONAL ANALYSIS OF PWB/COMPONENT GEOMETRYCUSTOMER:PRODUCT:
DEVICE GEOMETRY - TSSOP24
0.44 mm 0.44 mm ("T") . ("T")
6.400 mm("L")
5.5 mm(S")
PWB LAND PATTERN DESIGN (PWB GEOMETRY)
PWB Pad PWB Pad
1.440 mm 4.320 mm 1.440 mm("Y") ('G') ("Y")
7.2 mm('Z')
RESULTS OF ANALYSIS
TOE TO TOE DIST = 7.200mm
TOE FILLET = 0.400mm or 16.00 mils
HEEL FILLET = 0.598mm or 23.92 mils
Acceptable Minimum Front and Back Fillets: 0.254 mm or 10 mils
TSSOP24
Fig 2 - TSSOP24
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THE FOLLOWING IS THE OPTIMUM PWB LAND PATTERN DESIGN:
Y = 1.74 MM
G = 3.92 MM Z = 7.40 MM
Y = 1.74 MM
LAND PATTERN DESIGN CALCULATION FROM THE DIMENSIONS GIVEN IN IPC-SM-782A SPECIFICATION
COMPONENT DIMENSIONS LAND PATTERN DIMENSIONS TOE AND HEEL FILLETSL Min L Max S Min S Max T Min Tmax Z G Y Toe Max Toe Min Heel Min
NOT AVAILABLE IN IPC-SM-782A
LAND PATTERN DESIGN FROM GIVEN NOMINAL PACKAGE DIMENSIONSCalculation of PWB Dimensions (Z, G and Y) with Desirable Heel and Toe Fillets
L NOMINAL S NOMINAL T NOMINAL Z G Y NOMINAL TOE AND HEEL FILLETS6.40 mm 5.52 mm 0.44 mm 7.40 mm 3.92 mm 1.74 mm 0.50 mm 0.80 mm
0.635 mm or
0.025"
0.33 mm or
0.013"
0.304 mm or0.012"
Fig 2 - TSSOP24
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LAND PATTERN DESIGN CALCULATION FROM THE DIMENSIONS GIVEN IN IPC-SM-782A SPECIFICATION
TOE AND HEEL FILLETSHeel Max
NOT AVAILABLE IN IPC-SM-782A
LAND PATTERN DESIGN FROM GIVEN NOMINAL PACKAGE DIMENSIONS
NOMINAL TOE AND HEEL FILLETS0.80 mm
Graphic Representation
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X-Axis Direction
PWB
PWB Pad
Note: Each Division in the X-Axis = 0.1mm
Graphically, the above figure illustrates that there will be enough toe fillet but a small heel fillet.
Component Body
Graphic Representation
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PWB Pad