DC-DC Step-Down Converter, 600mA, 1.5MHz 0 pages
AS1324
1.5MHz, 600mA, DC/DC Step-Down Regulator
www.austriamicrosystems.com/DC-DC_Step-Down/AS1324 Revision 1.05 1 - 20
Datasheet
1 General Description
The AS1324 is a high-efficiency, constant-frequency synchronous
buck converter available in adjustable- and fixed-voltage versions.
The wide input voltage range (2.7V to 5.5V), automatic powersave
mode and minimal external component requirements make the
AS1324 perfect for any single Li-Ion battery-powered application.
Typical supply current with no load is 30ìA and decreases to 1ìA
in shutdown mode.
The AS1324 is available as the standard versions listed in Table 1.
An internal synchronous switch increases efficiency and eliminates
the need for an external Schottky diode. The internally fixed
switching frequency (1.5MHz) allows for the use of small surface
mount external components.
Very low output voltages can be delivered with the internal 0.6V
feedback reference voltage.
The AS1324 is available in a 5-pin TSOT-23 package.
Figure 1. Typical Application Diagram – High Efficiency Step
Down Converter
2 Key Features
! High Efficiency: Up to 96%
! Output Current: 600mA
! Input Voltage Range: 2.7V to 5.5V
! Constant Frequency Operation: 1.5MHz
! Variable- and Fixed-Output Voltages
! No Schottky Diode Required
! Automatic Powersave Operation
! Low Quiescent Current: 30ìA
! Internal Reference: 0.6V
! Shutdown Mode Supply Current: 1ìA
! Thermal Protection
! 5-pin TSOT-23 Package
3 Applications
The device is ideal for mobile communication devices, laptops and
PDAs, ultra-low-power systems, threshold detectors/discriminators,
telemetry and remote systems, medical instruments, or any other
space-limited application with low power-consumption requirements.
Table 1. Standard Versions
Model Output Voltage
AS1324-AD Adjustable via External Resistors
AS1324-12 Fixed: 1.2V
AS1324-15 Fixed: 1.5V
AS1324-18 Fixed: 1.8V
AS1324-18
COUT
10ìF
CIN
10ìF
2 GND
VIN = 2.7V to 5.5V 4.7ìH VOUT = 1.8V, 600mA
1
EN
5
VOUT
4
VIN
3
SW
5 VOUT
AS1324-18
4 VIN
GND 2
SW 3
EN 1