BQ2000 Datasheet, PDF (1/18 Pages) Texas Instruments – Programmable Multi-Chemistry Fast-Charge Management IC

bq2000
Programmable Multi-Chemistry
Fast-Charge Management IC
Features
➤ Safe management of fast
charge for NiCd, NiMH, or Li-
Ion battery packs
➤ High-frequency switching con-
troller for efficient and simple
charger design
➤ Pre-charge qualification for
detecting shorted, damaged, or
overheated cells
➤ Fast-charge termination by
peak voltage (PVD), minimum
current (Li-Ion), maximum
temperature, and maximum
charge time
➤ Selectable top-off mode for
achieving maximum capacity in
NiMH batteries
➤ Programmable trickle-charge
mode for reviving deeply dis-
charged batteries and for post-
charge maintenance
➤ Built-in battery removal and
insertion detection
➤ Sleep mode for low power
consumption
General Description
The bq2000 is a programmable,
monolithic IC for fast-charge manage-
ment of nickel cadmium (NiCd),
nickel metal-hydride (NiMH), or lith-
ium-ion (Li-Ion) batteries in single- or
multi-chemistry applications. The
bq2000 detects the battery chemistry
and proceeds with the optimal charg-
ing and termination algorithms. This
process eliminates undesirable under-
charged or overcharged conditions
and allows accurate and safe termi-
nation of fast charge.
Depending on the chemistry, the
bq2000 provides a number of charge
termination criteria:
n Peak voltage, PVD (for NiCd and
NiMH)
n Minimum charging current (f or
Li-Ion)
n Maximum temperature
n Maximum charge time
For safety, the bq2000 inhibits fast
charge until the battery voltage and
temperature are within user-defined
limits. If the battery voltage is
below the low-voltage threshold, the
bq2000 uses trickle-charge to
condition the battery. For NiMH
batteries, the bq2000 provides an
optional top-off charge to maximize
the battery capacity.
The integrated high-frequency com-
parator allows the bq2000 to be the
basis for a complete, high-efficiency
power-conversion circuit for both
nickel-based and lithium-based
chemistries.
Pin Connections
Pin Names
SNS
1
VSS
2
LED
3
BAT
4
8
MOD
7
VCC
6
RC
5
TS
8-Pin DIP or Narrow SOIC
or TSSOP
PN-2000.eps
SNS
VSS
LED
BAT
Current-sense input
System ground
Charge-status
output
Battery-voltage
input
TS
RC
VCC
MOD
Temperature-sense
input
Timer-program input
Supply-voltage input
Modulation-control
output
SLUS138B–FEBRUARY 2001 F
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