bq2002

Features:

Fast charge of nickel cadmium or nickel-metal hydride batteries
Direct LED output displays chargestatus
Fast-charge termination by -V,maximum voltage, maximum temperature, and maximum time
Internal band-gap voltage reference
Optionaltop-offcharge
Selectable pulse trickle charge rates
Low-powermode
8-pin 300-mil DIP or 150-mil SOIC


Pinout




Specifications

Symbol	Parameter	Minimum	Maximum	Unit	Notes
VCC	VCC relative to VSS	-0.3	+7.0	V
VT	DC voltage applied on any pin excluding VCC relative to VSS	-0.3	+7.0	V
TOPR	Operating ambient temperature	0	+70	°C	Commercial
TSTG	Storage temperature	-40	+85	°C
TSOLDER	Soldering temperature	-	+260	°C	10 sec max.
TBIAS	Temperature under bias	-40	+85	°C

Description

The bq2002 and bq2002/F Fast-Charge ICs are low-cost CMOS battery-charge controllers providing reliable charge termination for both NiCd and NiMH battery applications. Controlling a current-limited or constant-current supply allows the bq2002/F to be the basis for a cost-effective stand-alone or system-integrated charger. The bq2002/F integrates fast charge with optional top-off and pulsed-trickle control in a single IC for charging one or moreNiCdorNiMHbatterycells.


Fast charge is initiated on application of the charging supply or battery replacement. For safety, fast charge is inhibited if the battery temperature and voltage are outside configured limits.


Fast charge of bq2000T is terminated by any of thefollowing:
Peakvoltagedetection(PVD)
Negativedeltavoltage(-V)
Maximumvoltage
Maximumtemperature
Maximumtime


After fast charge, the bq2002/F optionally tops-off and pulse-trickles the battery per the pre-configured limits.Fast charge may be inhibited using the INH pin. This may also be placed in low-standby-power mode toreducesystempowerconsumption.


The bq2002F differs from it only in that a slightly different set of fast-charge and top-off time limits is available. All differences between the two ICs are illustratedinTable1.