AS1341
20V, 600mA, 100% Duty Cycle, Step-Down Converter
Data Sheet
www.austriamicrosystems.com Revision 1.00 1 - 16
1 General Description
The AS1341 is a high-efficiency step-down converter
with adjustable output voltages from 1.25V to VIN using
supply voltages of up to 20V.
An integrated current-limited 0.4Ω 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 effi-
ciency if input voltages is in the range of the output volt-
age.
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 pack-
age.
Figure 1. Ty pical Application
2 Key Features
! Output Voltages: Fixed 5V or Adjustable
! Input Voltage Range: 4.5 to 20V
! Output Current: Up to 600mA
! 1.25V Lowest Output Voltage
! Efficiency: up to 96%
! Quiescent Supply Current: 12µA
! Power-OK Output
! Internal 0.4Ω 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 bat-
tery-operated, portable device.
4.5 to 20V
5
IN
4
LX
1
FB
CIN
5V
AS1341
2
GND
8
OUT
D1
L1
COUT
+
Indicates High-Power Trace
3
POK
RPULL
5IN
3
POK
2GND
1FB 8OUT
AS1341
4LX
7 SHDNN
6
ILIMIT
9
7
SHDNN
6
ILIMIT
