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SEMI G2-94 © SEMI 1 994 6 Figure 1 Bow Figure 2 Camber Figure 3 Stamped Leadframe Terminology

SEMI G2-94 © SEMI 19945

Description Cavity Length Cavity Width Lead-Formed Width, Top

Bond Finger Layout

End vs. Side

Nominal

Progression Unit

24SD3M 0.430 ± 0.010 0.180 ± 0.010 0.311 ± 0.003 8 4 1.510 in

10.92 ± 0.254 4.57 ± 0.254 7.90 ± 0.076 38.35 mm

24SD4M 0.210 ± 0.010 0.210 ± 0.010 0.411 ± 0.003 6 6 1.510 in

5.33 ± 0.254 5.33 ± 0.254 10.44 ± 0.076 38.35 mm

28MSI 0.260 ± 0.011 0.260 ± 0.011 0.611 ± 0.003 8 6 1.724 in

6.60 ± 0.279 6.60 ± 0.279 15.01 ± 0.076 43.79 mm

28LSI 0.325 ± 0.011 0.275 ± 0.011 0.611 ± 0.003 8 6 1.724 in

8.26 ± 0.279 6.99 ± 0.279 15.01 ± 0.076 43.79 mm

28VLSI 0.420 ± 0.011 0.280 ± 0.011 0.611 ± 0.003 8 6 1.724 in

10.67 ± 0.279 7.11 ± 0.279 15.01 ± 0.076 43.79 mm

40MSI 0.270 ± 0.012 0.260 ± 0.012 0.611 ± 0.003 10 10 2.300 in

6.86 ± 0.305 6.60 ± 0.305 15.01 ± 0.076 58.42 mm

40LSI 0.375 ± 0.012 0.295 ± 0.012 0.611 ± 0.003 12 8 2.300 in

9.53 ± 0.305 7.49 ± 0.305 15.01 ± 0.076 58.42 mm

NOTE: While a 0.311 top form is still currently being used, numerous users have changed to a 0.314 top form to prevent interference between the

Cer-DIP base and leadframe.

Table 2

Leads Planarity Coplanarity

8–14–16 +0.003"/–0.004" (+ 0.076 mm/–0.102 mm) 0.004" (0.102 mm)

18 +0.004"/–0.005" (+0.102 mm/–0.127 mm) 0.005" (0.127 mm)

20 +0.004"/–0.005" (+0.102 mm/–0.127 mm) 0.006" (0.152 mm)

22 +0.004"/–0.006" (+0.102 mm/–0.152 mm) 0.006" (0.152 mm)

24 +0.004"/–0.006" (+0.102 mm/–0.152 mm) 0.007" (0.178 mm)

28 +0.005"/–0.007" (+0.127 mm/–0.178 mm) 0.008" (0.203 mm )

40 +0.006"/–0.008" (+0.152 mm/–0.203 mm) 0.010" (0.254 mm)

SEMI G2-94 © SEMI 1994 6

Figure 1

Bow

Figure 2

Camber

Figure 3

Stamped Leadframe Terminology

METHOD #1

METHOD #2

REF PLANE

Figure 4

Twist Strip

Using surface plate, establish a reference plane the whole length of the frame strip. Place frame strip, either method

1 or 2, whichever method gives a 3 point contact with reference plane A, using thickness gauges to determine height

between reference plane and 4th point noted as t. This measurement will determine frame twist over entire length.

Figure 5

Standoff Lead Length