BQ2005 Datasheet, PDF (4/16 Pages) Texas Instruments – Fast-Charge IC for Dual-Battery Packs

bq2005
The valid battery voltage range is VEDV < VBAT < VMCV.
The valid temperature range is VHTF < VTEMP < VLTF,
where:
VLTF = 0.4 ∗ VCC ± 30mV
VHTF = [(1/4 ∗ VLTF) + (3/4 ∗ VTCO)] ± 30mV
VTCO is the voltage presented at the TCO input pin, and is
configured by the user with a resistor divider between VCC
and ground. The allowed range is 0.2 to 0.4 ∗ VCC.
If the temperature of the battery is out of range, or the
voltage is too low, the chip enters the charge pending
state and waits for both conditions to fall within their al-
lowed limits. The MODA,B output is modulated to pro-
vide the configured trickle charge rate in the charge
pending state. There is no time limit on the charge
pending state; the charger remains in this state as long
as the voltage or temperature conditons are outside of
the allowed limits. If the voltage is too high, the chip
goes to the battery absent state and waits until a new
charge cycle is started.
Fast charge continues until termination by one or more
of the five possible termination conditions:
n Delta temperature/delta time (∆T/∆t)
n Negative delta voltage (-∆V)
n Maximum voltage
n Maximum temperature
n Maximum time
Dis-
Charge
charge Pending*
(Optional (Pulse-Trickle)
Battery A)
DIS_A
Fast Charging
Switch-mode
MOD_A,B Configuration
or
External
MOD_A,B Regulation
CH_A,B Status Output
Top-Off
(Optional)
4s
34s
4s
34s
FCC_A,B Status Output
Pulse-Trickle
260 s
Note*
260 s
Note*
Battery within temperature/voltage limits.
Battery discharged to 0.475 _* VCC. Battery outside
temperature/voltage limits.
Discharge-Before-Charge started
*See Table 3 for pulse-trickle period.
Figure 2. Charge Cycle Phases
T200501.eps
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