BQ2002D_14 Datasheet, PDF (3/17 Pages) Texas Instruments – NiCd/NiMH Fast-Charge Management ICs

bq2002D/T
Chip on
VCC 4.0V
Battery Voltage
too High?
VBAT < 2V
VTS > 0.25V VCC
Battery
Temperature?
VBAT _{> 2V}
VTS < 0.25V VCC
Charge
Pending
Fast Charge,
CC = Z
LED = Low
Off,
CC = Low
VBAT < 2V and
LED = Low
VTS > 0.25V VCC
VBAT > 2V
T/ t or
VBAT > 2V or
VTS < 0.25V VCC or
Maximum Time Out
VBAT 2V
Off,
CC = Low
LED = Z
SD2002D.eps
Figure 2. bq2002D State Diagram
Chip on
VCC 4.0V
Battery Voltage
too High?
VBAT < 2V
0.25 VCC < VTS < 0.4 VCC
Battery
Temperature?
( T/ t or
Maximum Time Out)
and TM = High
Top-off
LED = Z
VBAT > 2V or
VTS < 0.225 VCC or
Maximum Time Out
Fast
LED =
Low
VBAT > 2V or
VTS < 0.225 VCC or
(( T/ t or
Maximum Time Out)
and TM = High)
VBAT _{> 2V}
VTS > 0.4 VCC or
VTS < 0.25 VCC
Charge
Pending
Trickle
LED =
VBAT < 2V and
Low
VTS < 0.4 VCC and VBAT > 2V
VTS > 0.25 VCC
VBAT 2V
Trickle
LED = Z
SD2002T.eps
Figure 3. bq2002T State Diagram
3