AS1320

200mA Step-Up DC-DC Converter

www.austriamicrosystems.com

Revision 1.0

Product Brief

1 General Description

The AS1320 is a high-efficiency step-up DC-DC con-

verter designed to generate a fixed voltage of +3.3V.

The AS1320 achieves an efficiency of up to 90%. The

minimum input voltage is 1.5V, the output voltage is

fixed at 3.3V, and output current is up to 200mA (@ 2V).

In order to save power the AS1320 features a shutdown

mode, where it draws less than 1µA. In shutdown mode

the battery is connected directly to the output enabling

the supply of real-time-clocks.

The AS1320 provides a power-on reset output that goes

high-impedance when the output reaches 90% of its reg-

ulation point.

The SHDNN trip threshold of the AS1320 can be used

as an input voltage detector that disables the device

when the battery voltage falls to a predetermined level.

An internal synchronous rectifier is included, thus an

external transistor or Schottky diode is not required.

The AS1320 is available in a 6-pin SOT23 package.

Figure 1. Application Diagram

2 Key Features

!

Fixed Output Voltage: 3.3V

!

Output Current: Up to 200mA (@ 2V)

!

Internal Synchronous Rectifier

!

Requires No External Schottky Diode or FETs

!

Shutdown Mode Supply Current: Less Than 1µA

!

Efficiency: Up to 90%

!

Minimum Input Voltage: +1.5V

!

Accurate Shutdown Low-Battery Cutoff Threshold

!

Battery Input Connected to Pin OUT in Shutdown

Mode for Backup Power

!

6-pin SOT23 Package

3 Applications

The AS1320 is ideal for low-power applications where

ultra-small size is critical as in medical diagnostic equip-

ment, hand-held instruments, pagers, digital cameras,

remote wireless transmitters, cordless phones, and PC

cards.

The device is also perfect as a local 3.3V supply or as a

battery backup.

AS1320

+1.5 to +3.5V

Battery

+3.3V

Output

22µF

22µF

L1

10µH

RESETN

Output

100k

Ω

On

Off

4

LX

3

GND

2

BATT

6

RESETN

1

SHDNN

5

OUT