AS1334
650mA, Ultra low Ripple Step Down DC/DC Converter
www.austriamicrosystems.com Revision 1.04 1 - 17
Datasheet
1 General Description
The AS1334 is a step-down DC-DC converter designed
to power portable applications from a single Li-Ion
battery. The device also achieves high-perfo r mance in
mobile phones and other applica tions requiring low
dropout voltage.
The AS1334 operates from an input voltage range of 2.7
to 5.5V whil e providi n g ou tput voltages of 1.2, 1.5, 1. 8,
2.5, 3.0 and 3.3V.
Fixed-frequency PWM operation minimizes RF
interference. Shutdown function turns the device off and
reduces battery consumption to 0.01µA (typ.).
The AS1334 is available in a TDFN(3x3) 8-pin package.
A high switching frequency (2 MHz) allows use of tiny
surface-mount components. Only three small external
surface-mount components, an inductor and two
ceramic capacitors are required.
2 Key Features
! Output Voltage Ripple: 2mV
! PWM Switching Frequency: 2MHz
! Single Lithium-Ion Cell Operation
! Output Voltage Range: 1.2V to 3.4V
(available in 100mV steps, see Ordering Information
on page 16)
! Fixed Output Voltages:
- 1.2V, 1.5V, 1.8V, 2.5V, 3.0V, 3.3V
! Maximum Load Capability of 650 mA
! 97% High Efficiency, 94% Average Efficiency
! Current Overload Protection
! Thermal Overload Protection
! Power-OK
! Soft Start
! Low Dropout Voltage (140 mΩ Typ PFET)
! TDFN(3x3) 8-pin
3 Applications
The AS1334 is an ideal solution to supply noise
sensitive applications as cellular phones, hand-held
radios, RF PC cards, battery powered RF devices, RFID
chipsets, A/D Converter, Sensors and OpAmps.
Figure 1. AS1334 - Typical Application Circuit
AS1334
PGND
SGND
EN
PVIN
VDD
SW
FB
10 µF
3.3 µH
V
OUT
VIN
10 µF
ON
OFF
POK
