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BA3662CP-V5

Datasheet

TSZ02201-0R6R0A600110-1-2

26.Jun.2012 Rev.001

© 2012 ROHM Co., Ltd. All rights reserved.

TSZ22111･15･001

www.rohm.com

●Power Dissipation

When using at temperatures over Ta=25℃, please refer to the heat reducing characteristics shown in Fig.15.

The IC characteristics are closely related to the temperature at which the IC is used, so it is necessary to operate the IC

at temperatures less than the maximum junction temperature Tjmax.

Fig.15 shows the acceptable loss and heat reducing characteristics of the TO220CP-V5 package. Even when the ambient

temperature Ta is a normal temperature (25℃), the chip (junction) temperature Tj may be quite high so please operate the

IC at temperatures less than the acceptable loss Pd.

The calculation method for power consumption Pc(W) is as follows.

Pc=(Vcc－Vo)×Io+Vcc×Ib

Acceptable loss Pd≧Pc

Solving this for load current Io in order to operate within the acceptable loss,

(Please refer to Fig.9 for Ib.)

design.

Calculation Example)

When Ta=85℃,Vcc=10V,Vo=5V

Please refer to the above information and keep thermal designs within the scope of acceptable loss for all operating

temperature ranges. The power consumption Pc of the IC when there is a short circuit (short between Vo and GND) is :

Pc=Vcc×(Ib+Ishort)

(Please refer to Fig.5 for Ishort.)

Io≦

Pd－Vcc×Ib

Vcc－Vo

With the IC alone :θja=62.5℃/W → -16mW/℃

25℃=2.0W → 85℃=1.04W

Vcc:

Vo:

Io:

Ib:

Ishort:

Input voltage

Output voltage

Load current

Circuit current

Short current

Io≦192mA (Ib:8mA)

Io≦

1.04－10×Ib

5

Fig.15

0

5

10

15

20

25

0

25

50

75

100

125

150

Ambient Temperature Ta(℃)

(1) 20.0

(2) 2.0

(1)When using a maximum heat sick : θjc=6.25(℃/W)

(2)When using an IC alone : θja=62.5(℃/W)