SC802 Datasheet, PDF (1/16 Pages) Semtech Corporation – Fully Integrated Lithium-Ion Battery Charger System with Timer

SC802/SC802A
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.
Typical Application Circuit
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
Applications
‹ Cellular phones
‹ PDA’s
‹ Handheld meters
‹ Charging stations
‹ Handheld computers
‹ Digital cameras
‹ Programmable current source
CHARGER VIN
C1
1uF
R3
R
RT1
THERMISTOR
t
R2
R1
SC802
14
11
13
3
7
4
8
VCC
CPB
VCC CHRGB
IPRGM RTIM
EN/NTC VPRGM
ITERM BSEN
10
12
2
1
16
6 ^BIPB
VOUT ₁₅
5
GND
RFGND
VOUT
AFC
9
ADC Iset
BATTERY
R4
C2
2. 2uF
CHARGE
R5
1K
CHARGER
PRESENT
R6
1K
June 13, 2005
1
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