PRELIMINARY AIC1821
ONE-CELL LITHIUM-ION BATTERY PROTECTION IC
SPEC NO: DS-1821-P1 06/07/00
ANALOG INTEGRATIONS CORPORATION www.analog.com.tw
4F, 9 Industry E. 9th Road, Science-based Industrial Park , Hsinchu, Taiwan, R.O.C. TEL: (8863)577-2500 FAX:(8863)577-2510 1
n FEATURES
l Reduction in Board Size due to Miniature Package
SOT-25 and Less External Components.
l Ultra-Low Quiescent Current at 7µA (VCC=3.5V).
l Ultra-Low Power-Down Current at 0.4µA (VCC
=2.3V).
l Precision Overcharge Protection Voltage
4.35V ± 30mV for the AIC1821A
4.30V ± 30mV for the AIC1821B
4.25V ± 30mV for the AIC1821C
4.20V ± 30mV for the AIC1821D
l Built-in Delay Time Circuits for Overcharge, Over-
discharge, and Overcurrent Protection.
l Load Detection Function during Overcharge Mode.
l Two Detection Levels for Overcurrent Protection.
n APPLICATIONS
l Protection IC for One-Cell Lithium-Ion Battery
Pack.
n DESCRIPTION
The AIC1821 battery protection IC is designed to
protect lithium-ion battery from damage or
degrading the lifetime due to overcharge,
overdischarge, and/or overcurrent for one-cell
lithium-ion battery powered systems, such as
cellular phones. The ultra-small package and less
required external components make it ideal to
integrate the AIC1821 into the limited space of
battery pack.
The accurate ±30mV overcharging detection
voltage ensures safe and full utilization charging.
Three different specification values for overcharge
protection voltage are provided for various
protection requirements. The very low standby
current drains little current from the cell while in
storage.


n TYPICAL APPLICATION CIRCUIT

BATT-
BATT+
100K
5 4
3
2
1
R2
R3
FUSE
C1
0.1µF
R1
100
10M
M2 SI9926
M1
SI9926
BATTERY
OC
CS
OD
GND
VCC
AIC1821
Protection Circuit for One-Cell Lithium-Ion Battery