BQ2004 Datasheet, PDF (8/15 Pages) Texas Instruments – Fast-Charge IC

bq2004
New Charge Cycle Started by
Any One of:
VCC Rising to Valid Level
Battery Replacement
(VCELL Falling through VMCV)
Inhibit (INH) Released
DCMD Tied to Ground?
No
VEDV < VCELL < VMCV
Battery Voltage?
Rising Edge
on DCMD
Yes
VCELL< VEDV Discharge-
Before-Charge
Battery Temperature?
Charge
Pending
VCELL < VEDV
VTEMP > VLTF or
VTEMP < VHTF
Pulse
Trickle
Charge
VCELL >
VMCV
VCELL > VMCV
VHTF < VTEMP < VLTF*
Fast
Charge
VCELL > VMCV
VEDV < VCELL < VMCV
and
VHTF < VTEMP < VLTF*
Pulse
Trickle
Charge
VCELL > VMCV
t > t_MCV
Battery
Absent
Pulse
Trickle
Charge
- V or
T/ t or
VTEMP < VTCO
or
Maximum Time Out
Top-Off
Selected?
Yes
No
VCELL >
VMCV
Top-Off
Charge
VCELL <
VMCV
VTEMP < VTCO
or Maximum
Time Out
VCELL >
VMCV
Charge
Complete
Pulse
Trickle
Charge
*VSEL = High disables LTF threshold enforcement
SD2004.eps
Figure 4. State Diagram
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