Jameco Electronics 2000 Tolerance And Solder Joint Analysis, Toe Fillet, Heel Fillet, Side Fillet

Models: 3000 2000

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TOLERANCE AND SOLDER JOINT ANALYSIS

Figure 5-3shows the PC board land pattern for the Rabbit 3000 chip in a 128-pin LQFP package. This land pattern is based on the IPC-SM-782 standard developed by the Surface Mount Land Patterns Committee and specified in Surface Mount Design and Land Pat- tern Standard, IPC, Northbrook, IL, 1999.

16.85mm (max.)

13.75mm (min.)

15.3 mm

12.4 mm

13.75 mm (min.)

16.85 mm (max.)

0.40 mm

 

0.28 mm (max.)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1.55 mm

12.4 mm

15.3 mm

TOLERANCE AND SOLDER JOINT ANALYSIS

JT: 0.29–0.55 mm

JH: 0.29–0.604 mm

Lmin

T

Smax

 

Zmax: 16.85 mm

 

Gmin: 13.75 mm

JS: -0.01–0.077 mm

Wmin

X: 0.28 mm

Toe Fillet (max.) Heel Fillet

Toe Fillet

Heel Fillet

Side Fillet

J:Solder fillet min/max (toe, heel, and side respectively)

L:Toe-to-toe distance across chip

S:Heel-to-heel distance across chip

T:Toe-to-heel distance on pin

W:Width of pin

Figure 5-3. PC Board Land Pattern for Rabbit 3000 128-pin LQFP

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Rabbit 3000 Microprocessor

Page 67
Image 67
Jameco Electronics 2000, 3000 manual Tolerance And Solder Joint Analysis, Toe Fillet, Heel Fillet, Side Fillet