BQ2005_13 Datasheet, PDF (1/18 Pages) Texas Instruments – Fast- Charge IC for Dual-Bat tery Packs

bq2005
Fast-Charge IC for Dual-
Battery Packs
Features
∗ Sequential fast charge and con d-i
tioning of two NiCd or NiMH nickel
cadmium or nickel-metal hydride
bat tery packs
∗ Hysteretic PWM switch-mode cur -
rent regulation or gated control of
an ex ter nal reg u la tor
∗ Easily integrated into systems or
used as a stand-alone charger
∗ Pre-charge qual i fi ca tion of tem per a-
ture and volt age
∗ Direct LED outputs dis play bat tery
and charge sta tus
∗ Fast-chargeterminationby
∆ temperature/∆ time, -∆V, max i mum
volt age, max i mum tem per a ture, and
max i mum time
∗ Optional top-off and pulse-trickle
charging
General Description
The bq2005 Fast-Charge IC provides
comprehensive fast charge control
functions together with high-speed
switching power control circuitry on a
monolithic CMOS device for sequential
charge man age ment in dual battery
pack ap pli ca tions.
In te gra tion of closed-loop cur rent con-
trol circuitry allows the bq2005 to be
the basis of a cost-effective solution
for stand-alone and sys tem-integrated
charg ers for bat ter ies of one or more
cells.
Switch-activated
dis-charge-before-charge allows
bq2005-based chargers to support bat-
tery conditioning and capacity determ-i
nation.
High-efficiency power con ver sion is ac-
complished using the bq2005 as a
hysteretic PWM controller for
switch-mode regulation of the charging
cur rent. The bq2005 may alternatively
be used to gate an externally reg u-
lated charging cur rent.
Fast charge may be gin on ap pli ca tion
of the charg ing sup ply, re place ment of
the battery, or switch depres sion. For
safety, fast charge is in hib ited un-
less/un til the bat tery tem per a ture and
volt age are within con fig ured lim its.
Temperature, voltage, and time are
monitored throughout fast charge.
Fast charge is ter mi nated by any of
the fol low ing:
n Rate of temperature rise
( ∆T/∆t)
n _{Negative delta voltage (-∆V)}
n Maximumvoltage
n _{Maximumtemperature}
n _Maximumtime
Af ter fast charge, op tional top-off and
pulsed current maintenance phases
are avail able.
Pin Connections
Pin Names
SLUS079A - AU GUST 2000 G
DCMD_A Dis charge com mand in put,
bat tery A
DVEN -DV en able
TM1 Timer mode se lect 1
TM2 Timer mode se lect 2
TCO Temperaturecut-off
TS_A, Tem pera ture sense in put,
TSB
bat tery A/B
BATA, Batteryvoltageinput,
BAT_B batteryA/B
SNSA, Sense re sis tor in put ,
SNSB batteryA/B
DIS_A
Dis charge con trol out put,
bat tery A
CHA,
CH_B
Charge status out put,
bat tery A/B
FCC_A, Fast charge com plete out put,
FCC_B batteryA/B
V_SS
Sys tem ground
V_CC
5.0V ±10% power
MOD_A, Charge cur rent con trol
MODB out put, bat tery A/B
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