Use case of TPS65982 + BQ Battery Charger

Hi Tsuguhiko-san,

[1] The TPS65982 provides GPIO control that can be used to disable the barrel jack charging PFETS when a PD contract is in place. The sink path on each TPS65982 will protect reverse current flow from system to VBUS automatically.  The ACDRV could be used to control a set of NFETs to prevent reverse current flow into the barrel jack connector, however the system would have to know when there is a PD contract to determine if it should drive enable ACDRV. This should be capable by modifying the registers on the BQ24780, but I would double check with the battery charger team.

[2] We have an example for the barrel jack path and the TPS65982 power path that we can share by email. Please send an email to usbpowerdelivery@list.ti.com

Generally we feed the battery charger input from single or multiple Type-C PD charging ports. The system tend to get slightly more complex when wireless charging and barrel jack charging is added. 

[3] Yes this is assuming that the Type-C connector is always connected. 

Jacob

Asai-san,

If you use a PFET to enable and disable the Barrel Jack connection, it will be OFF when the Barrel Jack is suddenly removed.

The NFETs inside the TPS65982 will be ON when the PD contract is negotiated.

In your diagram, removing the Barrel Jack will not cause the system to die, but removing the Type-C connection may cause the system to brown-out.

Typically, we just use a Schottky diode to protect the Barrel Jack power supply from the PD Voltages that may be higher. This simple analog implementation prevents damage and brown-outs.