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AS1312

Datasheet - A p p l i c a t i o n I n f o r m a t i o n

9 Application Information

The AS1312 is available with fixed output voltages from 2.5V to 5.0V in 50mV steps.

Figure 11. AS1312 - Block Diagram

9.1 AS1312 Features

Shutdown.

The part is in shutdown mode while the voltage at pin EN is below 0.1V and is active when the voltage is higher than 0.7V.

Note:

Output Disconnect.

Feedthrough Mode.

If the input voltage is higher than the output voltage (and the AS1312 is enabled) the supply voltage is connected to the load through the device.

To guarantee a proper function of the AS1312 it is not allowed that the supply exceeds the maximum allowed input voltage (5.0V).

In this feedthrough mode the quiescent current is 35µA (typ.). The device goes back into step-up mode when the output voltage is 4% (typ.)

Zero

Crossing

Detector

AS1312

Driver

and

Control

Logic

Startup

Circuitry

6.8µH

0.7 to 5.0V

Input

Imax

Detection

22µF

+

–

2.5V to 5.0V

Output

22µF

LX

EN

VOUT

GND

REF

LBO

VIN

LBI

100nF