L6924U

Additional applications information

Doc ID 14716 Rev 2

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9

Additional applications information

9.1

Selecting the input capacitor

be used to filter the high frequency noise.

9.2

Selecting the output capacitor

keep

voltage control loop stable. This ensures proper operation of battery absent detection

in removable battery pack applications.

9.3

Layout guidelines and demonstration board

The thermal loop keeps the device at a constant temperature of approximately 120 °C which

ensure a good thermal path. Therefore, the exposed pad must be properly soldered to the

board and connected to the other layer through thermal vias. The recommended copper

thickness of the layers is 70

μm or more.

The exposed pad must be electrically connected to GND. Figure 22 shows the thermal

image of the board with the power dissipation of 1 W. In this instance, the temperature of the

case is 89 °C, but the junction temperature of the device is given by the following equation:

Equation 25

and the ambient temperature is 25 °C.

In this case the junction temperature is:

Equation 26

AMB

DISS

A

THJ

J

T

P

R

T

+

×

=

−

C

T

J

o

100

25

1

75

=

+

×

=