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BD3537F

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TSZ22111・15・001

TSZ02201-0J2J0A900970-1-2

02.Nov.2015 Rev.001

3.

Power Dissipation

In thermal design, consider the temperature range where IC is guaranteed to operate and appropriate margins. The

temperature conditions that need to be considered are listed below:

(1) Ambient temperature Ta: 100°C or lower

(2) Chip junction temperature Tj: 150°C or lower

The chip junction temperature Tj can be considered as follows:

Most of heat loss in BD3537F occurs at the output N-Channel FET. The lost power is determined by multiplying the

voltage between IN and OUT by the output current. Since this IC is packaged for high-power applications, its thermal

derating characteristics significantly depend on the PCB. So when designing, the size of the PCB to be used should be

carefully considered.





0.4(W)

=

0.5(A)

(V)

0.9

-

(V)

1.8

=

(W)

n

consumptio

Power



◎SOP8(BD3537F)

(1) 70mm x 70mm x 1.6mm Glass-epoxy PCB

θj-c=181°C/W

(2) With no heat sink

θj-a=222°C/W

150

[°C]

0.60

0

25

75

100

125

50

0.20

0.10

0

0.40

0.50

0.30

[W]

(2) 0.56W

100°C

(1) 0.69W

0.70

Ambient Temperature [Ta]