STBC21 Datasheet, PDF (14/54 Pages) STMicroelectronics – LI+ battery charger with thermal regulation

Detailed description
STBC21
Note:
Figure 4. Charging process flowchart
Insert BaƩery
BaƩery connecƟon
detecƟon at
beginning of charge
NO
VBAT < 1.0V
YES
TIMER-4 ON
TerminaƟon
(without
Auto-recharge)
YES
NO
VBAT < 3.9V
BaƩery ConnecƟon
DetecƟon
at the End of Charge
YES
NO _{Auto Recharge}
ON
YES
TIMER-3
NO
elapsed
0V-Charge Mode
NO
VBAT > 1.0V
YES
TIMER-1 ON
NO
TIMER-4
YES
elapsed
BaƩery alarm
Safe charge
TIMER-3 ON
NO
Safe charge
OFF
YES
(TIMER-3=0 min)
YES
NO
Auto Recharge
ON
BaƩery ConnecƟon
DetecƟon
at the End of Charge
Pre-Charge Mode
NO
VBAT > 3.0V
NO
TIMER-1
YES
elapsed
BaƩery alarm
YES
NO
IBAT < ISET3
YES
TIMER-2 ON
Fast-Charge Mode
in constant current
TerminaƟon
(without
Auto-recharge)
Fast-Charge Mode
in constant voltage
NO
BaƩery ConnecƟon YES _TIMER-2
YES
DetecƟon
at the End of Charge
elapsed
NO
VBAT < VFLOAT
TIMER-2
elapsed
NO
TerminaƟon
(without
Auto-recharge)
YES
BaƩery ConnecƟon
DetecƟon
at the End of Charge
TerminaƟon
(without
Auto-recharge)
AM10415v 1
Two outputs can be used to detect the status of charge. The functionality of these two pins
can be customized in NVM as outlined in Appendix E & Appendix F. This is to allow the final
customer to have different kinds of information depending on whether the output is ON, OFF,
or flickering. The flickering frequency is programmable both in frequency and duty cycle (see
Appendix E & Appendix F).
The device functionality is not guaranteed if the parameters are modified in NVM during the
charging cycle.
5.1
Operation mode
The STBC21 can work in standalone or driven by a microcontroller. If it works in standalone,
all device parameters are those stored in NVM. Otherwise, if it works driven by a
microcontroller, it is the microcontroller itself to program through I²C (SCL and SDA pins) the
device parameters.
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Doc ID 023256 Rev 1