BQ25302: BQ25302: Is Q1 (input FET from VBUS to PMID) disabled when /EN is high (disabled)?

Pieter Conradie

Part Number: BQ25302

Tool/software:

Hi there,

The BQ25302 is disabled when /EN is pulled high. This disables the charger functionality and can be used to reset a fault condition.

Is Q1 (input FET from VBUS to PMID) also disabled when /EN is high?

The application is where a PFET (Q4) is used for an external Power Path and the microcontroller is supplied from PMID (VSYS). If the microcontroller pulls the /EN pin high and Q1 switches off then it will be supplied via the body diode of Q1 with an increased voltage drop which is not ideal. I couldn't find any specs in the datasheet regarding the body diodes of the FETs.

Thanks in advance,

Pieter

9 months ago

0 Ning T 9 months ago

TI__Guru 56341 points

Hi Pieter,

What are the charger operating conditions such as VBUS (voltage at VBUS pin), IVBUS, VBAT (voltage at BAT pin), IBAT, VPMID and IPMID? What's your concern?

Thanks,

Ning.

0 Pieter Conradie 9 months ago in reply to Ning T

Prodigy 170 points

Hi Ning,

VBUS = +4.4V to +5.25V (supplied from USB). VBAT = 3.3V to 4.2V (Li-Ion battery). IPMID = 0mA to 500mA.

I just want to know: is Q1 off when /EN is high? If yes, what are the specs of Q1's body diode? Voltage drop and max current through the body diode?

Thanks in advance,

Pieter

+1 Ning T 9 months ago in reply to Pieter Conradie

TI__Guru 56341 points

Hi Pieter,

Q1 should be off.

Thanks,

Ning.

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BQ25302: BQ25302: Is Q1 (input FET from VBUS to PMID) disabled when /EN is high (disabled)?