BQ24040 Datasheet, PDF (7/31 Pages) Texas Instruments – 800mA Single-Input Single Cell Li-Ion Battery Charger With Auto Start

bq24040
bq24041
www.ti.com.................................................................................................................................... SLUS941A – SEPTEMBER 2009 – REVISED SEPTEMBER 2009
PIN CONFIGURATION
bq 24040
bq24041
1 IN
OUT ¹⁰
1 IN
OUT ¹⁰
2 ISET
TS ⁹
2 ISET
BAT_EN ⁹
3 VSS
CHG 8
3 VSS
CHG 8
4 PRETERM _ISET2 7
4 ASI
ISET2 ⁷
5 _PG
NC ⁶
5 _PG
ASO ⁶
NAME
IN
bq24040
1
bq24041
1
OUT
10
10
PRE-TERM
4
–
ISET
ISET2
2
2
7
7
TS
9 ⁽¹⁾
–
BAT_EN
VSS
CHG
PG
ASI
ASO
NC
Thermal
PAD and
Package
–
3
8
5
–
–
6
Pad
2x2mm²
9
3
8
5
4
6
–
Pad
2x2mm²
(1) Spins have different pin definitions
PIN FUNCTIONS
I/O DESCRIPTION
I
Input power, connected to external DC supply (AC adapter or USB port). Expected range
of bypass capacitors 1μF to 10μF, connect from IN to V_SS.
Battery Connection. System Load may be connected. Average load should not be
O excessive, allowing battery to charge within the 10 hour safety timer window. Expected
range of bypass capacitors 1μF to 10μF.
I
Programs the Current Termination Threshold (5 to 50% of Iout which is set by ISET) and
Sets the Pre-Charge Current to twice the Termination Current Level.
Expected range of programming resistor is 1k to 10kΩ (2k: Ipgm/10 for term; Ipgm/5 for
precharge)
I
Programs the Fast-charge current setting. External resistor from ISET to VSS defines fast
charge current value. Range is 10.8k (50mA) to 675 Ω (800mA).
Programming the Input/Output Current Limit for the USB or Adaptor source:
I bq24040 => High = 500mAmax, Low = ISET, FLOAT = 100mAmax.
bq24041 => High = 410mAmax, Low = ISET, FLOAT = 100mAmax.
Temperature sense pin connected to bq24040 -10k at 25°C NTC thermistor, in the battery
pack. Floating TS Pin or pulling High puts part in TTDM “Charger” Mode and disable TS
I monitoring, Timers and Termination. Pulling pin Low disables the IC. If NTC sensing is not
needed, connect this pin to VSS through an external 10 kΩ resistor. A 250kΩ from TS to
ground will prevent IC entering TTDM mode when battery with thermistor is removed.
I Charge Enable Input (active low); 200k Internal Pull-down
– Ground terminal
O
Low (FET on) indicates charging and Open Drain (FET off) indicates no Charging or
Charge complete.
O Low (FET on) indicates the input voltage is above UVLO and the OUT (battery) voltage.
I Auto start External input. Internal 200kΩ pull-down.
O Auto Start Logic Output
NA Do not make a connection to this pin (for internal use) – Do not route through this pin
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
Copyright © 2009, Texas Instruments Incorporated
Product Folder Link(s): bq24040 bq24041
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