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FPF2108-FPF2110 Rev. E

Application Information

Typical Application

OFF ON

ON

GND

FPF2108 - FPF2110

FLAGB

LOAD

Battery

1.8V-5.5V

C1 = 4.7µF

R1 = 100KΩ

C2 = 0.1

µF

R2 = 499Ω

Input Capacitor

To limit the voltage drop on the input supply caused by transient

in-rush currents when the switch turns-on into a discharged load

capacitor or a short-circuit, a capacitor needs to be placed

used to further reduce the voltage drop experienced as the

switch is turned on into a large capacitive load.

Output Capacitor

GND. This capacitor will prevent parasitic board inductances

Power Dissipation

During normal operation as a switch, the power dissipation is

small and has little effect on the operating temperature of the

part. The parts with the higher current limits will dissipate the

most power and that will only typically be,

When in current limit the maximum power dissipation will occur

when the output is shorted to ground. A short on the output will

cause the part to operate in a constant current state until the

thermal shutdown activates. It will then cycle in and out of

thermal shutdown so long as the ON pin is active and the short

is present.

Board Layout

For best performance, all traces should be as short as possible.

To be most effective, the input and output capacitors should be

placed close to the device to minimize the effects that parasitic

trace inductances may have on normal and short-circuit

minimize parasitic electrical effects along with minimizing the

case to ambient thermal impedance.

80mW

0.125

(0.8)

R

)

(I

P

2

2

DS

LIM

=

∗

=

∗

=