STBCFG01

Operation description

DocID026474 Rev 3

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The device also features an output overvoltage protection which turns off OTG boost if the

boost is disabled and an alarm is generated.

Together with the standard cycle-by-cycle current limit for the inductor peak current, the

STBCFG01 also implements an average battery current limitation to avoid excessive

battery voltage drop during peaks in system current consumption. When the average boost

OTG boost is disabled and an alarm is generated.

5.3

LDO regulator

The STBCFG01 integrates a 4.85 V, 50 mA LDO regulator which is active when DCIN

not connected and in OTG mode, while it is turned off in automatic shutdown conditions

protected against short-circuit.

5.4

Pre-bias

In order to allow proper functionality with input sources not integrating the necessary

minimum load to provide a valid voltage, the STBCFG01 integrates an automatic pre-bias

attempt reducing the input voltage down to a valid level. During the charging cycle, if the

pre-bias current has been activated, it is kept on only during trickle charge and taper

charge. The pre-bias current is also turned off in automatic shutdown conditions (ASD).

The pre-bias current is active only if the input voltage is in the activation range for at least

Figure 8: Pre-bias enable strategy