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AS1337

Datasheet - D e t a i l e d D e s c r i p t i o n

Shutdown

When pin EN is low the AS1337 is switched off and <1µA current is drawn from battery; when pin EN is high the device

intermittently switching the device on.

Note: If pin EN is not used, it should be connected directly to pin VOUT.

down. During normal operation the device is in down conversion mode.

Shutdown Battery Feedthrough (AS1337A)

In shutdown the battery input of the AS1337A is connected to the output through the inductor and the small internal

synchronous rectifier P-FET. This allows the input battery to provide backup power for devices such as an idle micro-

controller, memory, or real-time-clock, without the usual diode forward drop. In this way a separate backup battery is

not needed.

Shutdown Battery Disconnect (AS1337B)

The AS1337B is designed to allow true output disconnect by opening both P-channel MOSFET rectifiers. During Shut-

POK Function

The POK output indicates if the output voltage is within 88% (typ.) of the nominal voltage level. As long as the output

age drops below 88% (typ.) of the nominal voltage the POK pin is pulled to GND.