BQ2002ESNTR Datasheet, PDF (3/15 Pages) Texas Instruments – NiCd/NiMH Fast-Charge Management ICs

bq2002E/G
Chip on
VCC 4.0V
Battery Voltage
too High?
VBAT > 2V
VBAT < 2V
Battery Voltage
too Low?
VBAT < 0.175 VCC
0.175 VCC < VBAT
VTS > 0.6 VCC
Battery
Temperature?
VTS < 0.6 VCC
(PVD or - V or
Maximum Time Out)
and TM = Low
Top-off
LED = Z
VBAT 2V or
VTS VCC/2 or
Maximum Time Out
Charge
Pending
Fast
Trickle
LED =
LED =
Low
VBAT > 0.175 VCC, Flash
VBAT > 2V or
VBAT < 2V, and
VTS > VCC/2
VBAT > 2V
VTS < VCC/2 or
((PVD or - V or
Maximum Time Out)
and TM Low)
VBAT 2V
Trickle
LED = Z
SD2002C.eps
Figure 2. State Diagram
OSC
TM
INH
Clock
Phase
Generator
Timing
Control
Sample
History
Voltage
Reference
Charge-Control
State Machine
Power-On
Reset
PVD, - V
ALU
A to D
Converter
LBAT
Check
MCV
BAT
HTF TCO _Power ^Check
Check Check _Down
CC
LED
TS
VCC
VSS
Bd2002CEG.eps
Figure 3. Block Diagram
3