Features

➤ Fast charge of nickel cadmium

or nickel-metal hydride batteries

➤ Direct LED output displays

charge status

➤ Fast-charge termination by -ΔV,

maximum voltage, maximum

temperature, and maximum

time

➤ Internal band-gap voltage reference

➤ Optional top-off charge

➤ Selectable pulse trickle charge

rates

➤ Low-power mode

➤ 8-pin 300-mil DIP or 150-mil

SOIC

General 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

more NiCd or NiMH battery cells.

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 is terminated by any of

the following:

Peak voltage detection (PVD)

Negative delta voltage (-ΔV)

Maximum voltage

Maximum temperature

Maximum time

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. The bq2002/F may also

be placed in low-standby-power mode

to reduce system power consumption.

The bq2002F differs from the

bq2002 only in that a slightly different

set of fast-charge and top-off

time limits is available. All differences

between the two ICs are illustrated

in Table 1.