TUSB321: Battery Charger IC with TUSB321 in UFP Mode

Matt Staniszewski

Part Number: TUSB321
Other Parts Discussed in Thread: BQ24073, BQ24192I

Hi,

I'd like to connect the OUT1/2 pins of the TUSB321 in UFP mode to a battery IC such that the charger IC is limited by the current limit supported on the USB-C port. Is there a battery IC that can do that?

Matt

over 6 years ago

0 Matt Staniszewski over 6 years ago

Intellectual 360 points

Took a look and I'm debating whether to use a charger IC like the bq24192I that has built-in selection pins for 500mA and 1.5A capability (I don't need 3A) or using a set of resistors and FETs to change the ILIM resistor value on a part such as the bq24073. I'm not sure if ILIM gets polled only at startup or continuously. Any thoughts?

0 Malik Barton57 over 6 years ago in reply to Matt Staniszewski

TI__Guru 64326 points

Hi Matt,

Connecting TUSB321 OUT1/1 directly to the ILIM pins will probably not work as battery charger need a current reference on the ILIM pin, which a resistor to ground provides. TUSB321 OUT1/2 will not be able to provide a adjustable current reference for your needs directly to the ILIM pin. However OUT1/2 can be used to help control some external circuit to set your charging current. I will send this over to the battery charger team to give any further reply please allow 1 - 2 business days for a further reply.

0 Matt Staniszewski over 6 years ago in reply to Malik Barton57

Intellectual 360 points

Hi Malik,

Thank you for your input, I'll look forward to their reply. I'm also considering using the OUT1/2 signals to drive FETs that switch the resistor value on ILIM. As long as ILIM is regularly polled, could this be another possibility?

Best,
Matt