SC802/SC802A
Fully Integrated Lithium-Ion
Battery Charger System with Timer
POWER MANAGEMENT
Features
Integrated charger with pass FET, reverse-blocking
diode, sense resistor, timer, and thermal protection
Battery Voltage — 4.1V, 4.2V, and adjustable
Programmable pre-charge, fast-charge, & termina-
tion current
Battery voltage controlled to 1% accuracy
Soft-start for glitch-free adaptor plug-in
Continuous charge current — Up to 1.5A
Charge current monitor output for microcontroller or
ADC interface
Input voltage range — 4.3V to 14V
Battery Drain when not charging — 0.1μA
Operates without a battery in regulated LDO mode
Small 4 x 4(mm) 16 lead MLPQ package
NTC thermistor sense input
Adjustable up to 6 Hour programmable charge timer
Over-current protection in all charging states
Over-voltage protection
Remote Kelvin sensing at the battery terminals
ADC input current control capable
Status output for charging and end of charge cycle
Charges Li-Ion, Li-Polymer, NiCd, and NiMH Batteries
Description
The SC802 and SC802A are fully integrated, single cell,
constant-current/constant-voltage Lithium-Ion/Lithium
Polymer battery chargers. With an integrated timer and
complete charge control algorithm, the devices are opti-
mized for stand-alone charger applications. They provide
for programmable pre-charge, fast-charge, and termina-
tion current settings. The devices can be programmed to
terminate the charge cycle 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
modified with the analog fast-charge input to allow a
Power Management Controller to control the fast-charge
current setting via DAC.
The 14V input voltage range of the SC802 and SC802A
eliminates additional protection circuitry required by
other 5V chargers in the event of faulty adapters.
Reference ground and battery sense inputs are provided
to allow Kelvin connections, to eliminate errors due to I×R
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 and SC802A can also function as a general purpose
current sources, such as for charging nickel-cadmium
(NiCd) and nickel-metal-hydride (NiMH) batteries.
The SC802A version of the device is optimized for high
termination current applications.
Applications
Cellular phones and PDA’s
Handheld meters
Charging stations
Handheld computers
Digital cameras
Programmable current source
Typical Application Circuit
CHARGER VIN
SC802/SC802A
CPB
VCC1
CHRGB
VCC2
RTIME
IPRGM
EN_NTC VPRGM
BSEN
ITERM
VOUT1
BIPB
VOUT2
GND
AFC
RFGND
R
ITERM
AFC I
SET
CHARGER
PRESENT
R
NPU
CHARGE
R
IPRGM
C
VCC
1μF
R
NTC
Battery
Thermistor
BAT.
C
VOUT
2.2μF
R
RTIME
October 30, 2008
© 2008 Semtech Corporation
1
SEMTECH [ SEMTECH CORPORATION ]
