STBC03

Functional pin description

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6.13

CHG

Active low, open drain charging/fault flag output pin. The CHG provides status information

about VIN voltage level, battery charging and faults by toggling at different frequencies as

reported in the table below.

Table 8: CHG pin state

Device state

CHG pin state

Note

High Z (high by

external pull-up)

In case of synchronous alarm events, the highest toggling

frequency has higher priority.

Example: NTC warning and EOC are concurrent events.

NTC warning, signaled by toggling CHG at 16.2 Hz is the

only signal available till the battery temperature goes back

to a safe range (0 °C to 45 °C). If an EOC condition is still

present then a 4.1 Hz toggling signal is present.

and CEN low)

Low

End-of-charge

(EOC)

Toggling 4.1 Hz

(until USB is

disconnected)

Charging phase (pre

and fast)

Toggling 6.2 Hz

Overcharge fault

Toggling 8.2 Hz

Charging timeout

(pre-charge, fast

charge)

Toggling 10.2 Hz

Battery voltage

fast charge starts

Toggling 12.8 Hz

Charging thermal

limitation (thermal

warning)

Toggling 14.2 Hz

Battery temperature

fault (NTC warning)

Toggling 16.2 Hz

6.14

CEN

Internal CC/CV charger block enable pin. A low logic level on this pin disables the internal

CC/CV charger block. Transitioning CEN from high to low and then back to high, allows the

CC/CV charger block to be restarted if it was stopped due to one of the following

conditions:



Charging timeout (pre-charge, fast charge)





End-of-charge

CEN has no effect if the charging cycle has been stopped by a battery overcharge

condition.

If the CC/CV charger stops the charging cycle due to an out of range battery temperature,

a low logic level on the CEN pin disables the CC/CV charger and resets the charging

timeout timers. If CEN is set high, the CC/CV charger restarts normal operations, assuming

that no fault condition is detected. CEN is internally pulled up to LDO via a 500 kΩ resistor

and must be either left floating or tied to LDO when the STBC03 is powered for the first

time. Should the auto-recharge function be enabled, the CC/CV charger restarts