AS1332
650mA, Step-Down DC-DC Converter for RF Power Amplifiers
Datasheet
www.austriamicrosystems.com Revision 1.01 1 - 19
1 General Description
The AS1332 is a step-down DC-DC converter designed
to power radiofrequency (RF) power amplifiers (PAs)
from a single Li-Ion battery. The device also achieves
high-performance in mobile phones and similar RF PA
applications.
The AS1332 steps down an input voltage of 2.7V to 5.5V
to output voltages ranging from 1.3V to 3.16V. Using a
V
CON
analog input, the output voltage is set for
controlling power levels and efficiency of the RF PA.
The RF interferences are minimized due to the fixed-
frequency PWM operation. The batter y consumption is
reduced to 0.01µA (typ.) during shutdown.
Because of the high switching frequencies (2 MHz) tiny
surface-mount components can be used. Additional to
the small size the amount is also small. On ly three
external components are required, an inductor and two
ceramic capacitors.
The AS1332 is available in a 8-pin WL-CSP.
2 Key Features
! PWM Switching Frequency: 2MHz
! Single Lithium-Ion Cell Operation (2.7V to 5.5V)
! Dynamic Programmable Outpu t Voltage (1.3V to
3.16V)
! Maximum load capability of 650mA
! High Efficiency (96% Typ at 3.6VIN, 3.16VOUT at
400mA) from internal synchronous rectification
! Current Overload Protection
! Thermal Overload Protection
! Soft Start
! 8-pin WL-CSP
3 Applications
The AS1332 is an ideal solution for cellular phones,
hand-held radios, RF PC cards, and battery powered RF
devices.
Figure 1. Typical Application Circuit
AS1332
PGND AGND
VCON
EN
PVIN
VDD
SW
FB
1.3V to 3.16V
V
OUT = 2.5 x VCON
4.7 µF
3.3 µH
V
OUT
2.7V to 5.5V
V
IN
10 µF
0.52V to 1.27V
V
CON