The heatsink for the LM6321 is made using the PC board

copper. The heat is conducted from the die, through the lead

frame (inside the part), and out the pins which are soldered

to the PC board. The pins used for heat conduction are:

TABLE 1.

Part

Package

Pins

LM6321N

8-Pin DIP

1, 4, 5, 8

LM6321M

14-Pin SO

1, 2, 3, 6, 7,

8, 9, 13, 14

Figure 3 shows copper patterns which may be used to dissi-

pate heat from the LM6321.

TABLE 2.

Package

L (in.)

H (in.)

θ

8-Pin DIP

2

0.5

47

14-Pin SO

1

0.5

69

21

57

Table 2 shows some values of junction-to-ambient thermal

resistance (

θ

8-Pin DIP

DS009223-9

14-Pin SO

DS009223-10

*For best results, use L = 2H

FIGURE 3. Copper Heatsink Patterns

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