BQ24212 Datasheet, PDF (2/8 Pages) Texas Instruments – 800mA, Single-Input, Single Cell Li-Ion Battery Solar Charger

bq24212
SLUSAL3 – AUGUST 2011
www.ti.com
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
DESCRIPTION (CONTINUED)
The charger power stage and charge current sense functions are fully integrated. The charger function has high
accuracy current and voltage regulation loops, charge status display, and charge termination function. The
charge current value is programmable via an external resistor.
Furthermore, the IC has a Load Mode that connects the battery to VBUS pin with current limiting function to
prevent over load. To use Load Mode, the charging source would be removed from the VBUS pin. Then a load
can be placed on VBUS pin and it will be near the VBAT pin voltage.
PIN CONFIGURATION
Figure 1. DQC PACKAGE
Top View
1 VBUS
BAT ¹⁰
2 ISET
VDPM ⁹
3 VSS
CHG 8
4 _VTSB
MODE ⁷
5 TS
PG ⁶
PIN
NAME
NO.
VBUS
1
BAT
10
VDPM
9
ISET
2
PG
6
TS
5
VSS
3
CHG
8
MODE
7
VTSB
4
Thermal
–
PAD and
Package
PIN FUNCTIONS
I/O
DESCRIPTION
I/O For Charging Mode, input for charging source, connect to external DC supply (ie Solar Panel, Inductive
charging PAD, or Wall Adapter)
For Load Mode, output for current limited battery voltage. Expected range of bypass capacitors 1µF to 10µF,
connected from VBUS to VSS.
I/O Battery Connection. System Load may be connected. Expected range of bypass capacitors 1μF to 10μF,
connected from BAT to VSS.
I Programs the input voltage regulation threshold. Expected range of programming resistor is 1k to 10kΩ,
connected from VDPM to VSS. When VDPM is floating, the VIN DPM loop operates in battery tracking mode,
and the VIN DPM threshold is BAT+100mV (BAT>3.6V) or 3.7V (BAT≤3.6V) in this case. VIN DPM threshold
should be programmed higher than battery voltage to ensure proper operation.
I Programs the Fast-charge current setting. External resistor from ISET to VSS defines fast charge current value.
O Power Present indication. LOW (FET ON) When input voltage is in normal range (VBUS>BAT & VBUS>UVLO),
High impedance (open drain FET OFF) in other cases.
I Temperature sense pin, connected to NTC Thermistor in the battery pack. Pulling High puts part in Limited
Power charging mode. Must not be left floating.
– Ground terminal
O Charge Status indication, Low (FET ON) indicates charging, and High impedance (open drain FET OFF) in
other cases
I Mode control. Low to enable Charge Mode or High to enable Load mode.
O TS bias reference voltage pin, regulated output. No external capacitor is required from VTSB to VSS. Only
enabled during charge.
– There is an internal electrical connection between the exposed thermal pad and the VSS pin of the device. The
thermal pad must be connected to the same potential as the VSS pin on the printed circuit board. Do not use
the thermal pad as the primary ground input for the device. VSS pin must be connected to ground at all times.
2
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