DESCRIPTION

This power supply IC incorporates a 4-channel series regulator and a battery backup function. It is a multi-function power supply IC with an output control function and momentary power-loss detection circuit, which are both required for mobile telephones. It also incorporates a speaker amplifier and a buzzer driver. Since it has a built-in power system suitable for mobile telephones, it promises equipment downsizing.

FEATURES

Power consumption during standby : 0.22 mW (typ.)

4-channel low-saturation voltage type : 6 W typ. for channels 1-3

series regulator 20 W typ. for channel 4

Battery backup function

Momentary power-loss and power-restoration functions

ON/OFF switch circuit with an operating error prevention function

BTL amplifier for driving the speaker : Output power= 90 mW typ.

Buzzer driver to permit changing the sound volume : 200 mA max.

Power supply voltage drops are accurately detected.

Hysteresis is provided for detection voltage.

Watchdog timer stop function is provided (inhibit pin).

Watchdog monitoring time and reset time are set independently.