www.ams.com/DC-DC_Step-Up/AS1341

Revision 1.09

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1 General Description

The AS1341 is a high-efficiency step-down converter with adjustable

20V.

An integrated current-limited 0.4

Ω MOSFET delivers load currents

up to 600mA.

The AS1341 also includes a 100% duty cycle LDO mode with a low

dropout of only 250mV for high efficiency if input voltages is in the

range of the output voltage.

The AS1341 has a low quiescent current (12µA) to improve light-

load efficiency and minimize battery use, and draws only 0.8µA in

shutdown mode.

High switching frequencies (up to 200kHz) allow the use of small

surface-mount inductors and output capacitors.

The device is available in a TDFN-8 3x3mm pin package.

Figure 1. AS1341 - Typical Application

2 Key Features

Output Voltages: Fixed 5V or Adjustable

Input Voltage Range: 4.5V to 20V

Output Current: Up to 600mA

1.25V Lowest Output Voltage

Efficiency: up to 96%

Quiescent Supply Current: 12µA

Power-OK Output

Internal 0.4

Ω P-Channel MOSFET

Shutdown Current: 0.8µA

100% Maximum Duty Cycle for Low Dropout

Current-Limited Architecture

Thermal Shutdown

TDFN-8 3x3mm Package

3 Applications

The device is ideal for notebook computers, distributed power

systems, keep-alive supplies, and any other battery-operated,

portable device.

4.5V to 20V

5

IN

1

FB

AS1341

2

GND

8

OUT

D1

+

Indicates High-Power Trace

3

POK

7

SHDNN

6

ILIMIT

4

LX

L1