AIC1620/AIC1621/AIC1622
High Efficiency Synchronous Step-Up DC/DC
Converter
n
FEATURES
l
n
DESCRIPTION
The AIC1620/AIC1621/AIC1622 are high effi-
ciency step up DC-DC converter. The start-up
voltage is as low as 0.8V and operate with an
input voltage down to 0.7V. Consuming only
20µA of quiescent current. These devices offer
a built-in synchronous rectifier that reduces
size and cost by eliminating the need for an ex-
ternal Schottky diode and improves overall effi-
ciency by minimizing losses.
The switching frequency depends on the load
and the input voltage can range up to 500KHz.
The peak current of the internal switch is fixed
at 0.8A (AIC1620), at 0.45A (AIC1621), or is
selectable (AIC1622) for design flexibility. Rip-
ple does not exceed the product of the switch
current limit and the filter capacitor equivalent
series resistance (ESR). The AIC1622 also fea-
tures a circuit that eliminates noise due to in-
ductor ringing.
High Efficiency 93% (V
IN
=2.4V, V
OUT
=3.3V,
I
OUT
=200mA).
20µA Quiescent Supply Current.
Power-Saving Shutdown Mode (0.1µA typical).
Internal Synchronous Rectifier ( no external
diode )
Selectable Current Limit for Reduced Ripple
( AIC1622 ).
Low Noise , Anti-Ringing Feature ( AIC1622 )
On-Chip Low Battery Detector.
Low Battery Hysteresis
l
l
l
l
l
l
l
n
APPLICATIONS
l
l
l
l
l
l
Palmtop & Notebook Computers.
PDAs
Wireless Phones
Pocket Organizers.
Cameras.
1 to 2-Cell Hand-Held Devices
n
TYPICAL APPLICATION CIRCUIT
V
IN
+
100µF
OFF
SHDN
AIC1620
AIC1621
AIC1622
LX
OUT
22µH
Output 3.3V, or
Adj. (1.8V to 4.0V)
up to 300mA
ON
+
220µF
Low-Battery
Detect In
LBI
REF
0.1µF
LBO
FB
LBO
GND
FB
Low-Battery
Detect Out
Analog Integrations Corporation
4F, 9 Industry E. 9th Rd, Science-Based Industrial Park, Hsinchu, Taiwan
TEL: 886-3-5772500
FAX: 886-3-5772510
www.analog.com.tw
DS-1620-00 032502
1