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U l t r a L o w Q u i e s c e n t C u r r e n t , H y s t e r e t i c D C - D C S t e p - U p C o n v e r t e r

1 General Description

The AS1312 achieves an efficiency of up to 94% and is designed to

operate from a +0.7V to +5.0V supply, the output voltage is fixed in

50mV steps from +2.5V to 5.0V.

In order to save power the AS1312 features a shutdown mode,

where it draws less than 100nA. In shutdown mode the battery is not

connected to the output.

If the input voltage exceeds the output voltage the device is in a

feedthrough mode and the input is directly connected to the output

voltage.

In light load operation, the device enters a sleep mode when most of

the internal operating blocks are turned off in order to save power.

This mode is active approximately 50µs after a current pulse

provided that the output is in regulation.

The AS1312 also offers an adjustable low battery detection. If the

battery voltage decreases below a threshold defined by two external

resistors on pin LBI, the LBO output is pulled to logic low. LBO is

working as Power-OK when LBI is connected to GND.

The AS1312 is available in a 8-pin (2x2) TDFN and a 0.4mm pitch 8-

pin WL-CSP package.

Figure 1. AS1312 - Typical Application Diagram

2 Key Features

Input voltage range: 0.7V to 5.0V

Fixed output voltage range: 2.5V to 5.0V

Peak output current: 200mA

Quiescent current: 1µA

Shutdown current: < 100nA

Up to 94% efficiency

Output disconnect in shutdown

Adjustable low battery detection or Power-OK output selectable

No external diode or transistor required

Over temperature protection

Packages:

- 8-pin (2x2) TDFN

- 8-pin WL-CSP with 0.4mm pitch

3 Applications

The AS1312 is an ideal solution for handheld devices and battery

powered products.

0.7V to 5.0V

AS1312

GND

2.5V to 5.0V

EN

VIN

VOUT

LBO

LBI

On

Off

L1 = 6.8µH

LX

Low Battery Detect

REF