Fully Integrated Lithium-Ion
Battery Charger System with Timer
POWER MANAGEMENT
Description
The SC802 is a fully integrated, single cell, constant-cur-
rent/constant-voltage Lithium-Ion\Lithium Polymer bat-
tery charger. With an integrated timer and complete
charge control algorithm, the SC802 is well suited for
stand-alone charger applications. The SC802 contains
programmable pre-charge, fast-charge, and termination
current settings. The SC802 can be programmed to ter-
minate charge based on the output current or the time-
out of the programmable timer. The fast charge current
is typically set with an external resistor but can be modi-
fied with the analog fast charge input to allow a Power
Management Controller to control the fastcharge current
setting via DAC.
The 14V input voltage range of the SC802 eliminates
additional protection circuitry required by other 5V charg-
ers in the event of faulty adapters.
Reference ground and battery sense inputs are provided
to allow Kelvin connections to eliminate IR voltage drops
during charging.
The output voltage to the battery is controlled to within
1% of the programmed voltage for either 4.1V or 4.2V.
The SC802 can also function as a general purpose cur-
rent source or as a current source for charging nickel-
cadmium (NiCd) and nickel-metal-hydride (NiMH) batter-
ies using NTC termination.
The SC802A version of the device is optimized for high
termination current applications. All descriptions and text
refering to the SC802 also apply to the SC802A unless
otherwise noted.
SC802/SC802A
Features
Fully integrated charger with FET pass transistor,
reverse-blocking diode, sense resistor, timer, and
thermal protection
Complete voltage ranges of 4.1V, 4.2V & adjust-
able
Programmable precharge, fastcharge & termina-
tion current
Battery voltage controlled to 1% accuracy
Soft-start for glitch-free adaptor plug-in
Up to 1A continuous charge current
Charge current monitor output for microcontroller
or ADC interface
Input voltage range from 4.3V to 14V
0.1μA battery drain current in shutdown and
monitor modes
Operates without a battery in regulated LDO mode
Small 4mm x 4mm 16 lead MLP package
NTC thermistor sense input
Adjustable 6 Hour programmable charge timer
Over current protection in all charging modes
Over voltage protection
Remote Kelvin sensing at the battery terminals
ADC input control capable
Status output communicates charging and end of
charge cycle
Charges Li-Ion, Li-Polymer, NiCd and NiMH
Batteries
Cellular phones
PDA’s
Handheld meters
Charging stations
Handheld computers
Digital cameras
Programmable current source
Applications
Typical Application Circuit
CHARGER VIN
R3
R
14
13
3
7
4
8
6
5
R2
R1
SC802
VCC
CPB
VCC
CHRGB
RTIM
IPRGM
EN/NTC VPRGM
ITERM
BSEN
BIPB
VOUT
GND
VOUT
RFGND
AFC
11
10
12
2
1
16
15
9
CHARGE
CHARGER
PRESENT
C1
1uF
RT1
THERMISTOR
R4
C2
2.2uF
R5
1K
R6
1K
ADC Iset
BATTERY
t
June 13, 2005
1
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SEMTECH [ SEMTECH CORPORATION ]
