BQ2002E Datasheet, PDF (1/13 Pages) Texas Instruments – NiCd/NiMH Fast-Charge Management ICs

bq2002E/G
NiCd/NiMH Fast-Charge Management ICs
Features
® Fast charge of nickel cadmium
or nickel-metal hydride batter-
ies
® Direct LED output displays
charge status
® Fast-charge termination by -∆V,
maximum voltage, maximum
temperature, and maximum
time
® Internal band-gap voltage ref-
erence
® Optional top-off charge
® Selectable pulse trickle charge
rates
® Low-power mode
® 8-pin 300-mil DIP or 150-mil
SOIC
Pin Connections
General Description
The bq2002E and bq2002G Fast-
Charge ICs are low-cost CMOS bat-
tery-charge controllers providing reli-
able charge termination for both NiCd
and NiMH battery applications. Con-
trolling a current-limited or con-
stant-current supply allows the
bq2002E/G to be the basis for a cost-
effective stand-alone or system-inte-
grated charger. The bq2002E/G inte-
grates fast charge with optional top-off
and pulsed- trickle control in a single
IC for charging one or more NiCd or
NiMH battery cells.
Fast charge is initiated on application
of the charging supply or battery re-
placement. For safety, fast charge is
inhibited if the battery temperature
and voltage are outside configured
limits.
Pin Names
Fast charge is terminated by any of
the following:
n Peak voltage detection (PVD)
n Negative delta voltage (-∆V)
n Maximum voltage
n Maximum temperature
n Maximum time
After fast charge, the bq2002E/G op-
tionally tops-off and pulse-trickles the
battery per the pre-configured limits.
Fast charge may be inhibited using
the INH pin. The bq2002E/G may
also be placed in low-standby-power
mode to reduce system power con-
sumption.
The bq2002E differs from the
bq2002G only in that a slightly dif-
ferent set of fast-charge and top-off
time limits is available. All differ-
ences between the two ICs are illus-
trated in Table 1.
TM
1
LED
2
BAT
3
VSS
4
8
CC
7
INH
6
VCC
5
TS
TM
LED
BAT
V_SS
Timer mode select input
Charging status output
Battery voltage input
System ground
TS
Temperature sense input
V_CC
Supply voltage input
INH
Charge inhibit input
CC
Charge control output
8-Pin DIP or
Narrow SOIC
PN-200201.eps
bq2002E/G Selection Guide
Part No. LBAT
bq2002E 0.175 ∗
VCC
TCO
0.5 ∗
VCC
bq2002G 0.175 ∗ 0.5 ∗
VCC
VCC
HTF
0.6 ∗
VCC
0.6 ∗
VCC
LTF
None
None
-∆V PVD
Fast Charge
C/2
1C
2C
C/2
1C
2C
tMTO
200
80
40
160
80
40
Top-Off
None
C/16
None
None
C/16
None
Maintenance
C/32
C/32
C/32
C/32
C/32
C/32
2/99
1