STPM801 : Oring function

[valentin_kickmaker]

Hello,

I've developed a PCB utilizing the STPM801 driver and am interested in deactivating its Oring feature.

The device I'm working on is battery-powered and operates two BLDC motors. There's a specific requirement to maintain functionality when the motors are driven by an external source, allowing the battery to recharge from this energy. However, with the STPM801 driver's Oring feature active, it seems this capability might be compromised.

Is there a way to turn off the Oring feature in this driver? Additionally, if I opt not to install the second MOSFET, which is responsible for preventing reverse current, will the driver still function properly?

Thanks in advance,

Valentin

[MarcoG · Accepted solution]

Hello Valentin.

STPM801 was designed to provide both hot-swap and or-ing functions in architectures that should be protected from reverse current and big voltage changes.
It is not possible to disable one of the two functions and support the reverse current.
If you remove the ORING FET, the short circuit that would occur between the SOURCE and SENSE pins would be interpreted as a FAULT (see table 18) causing the pre-drivers to be disabled.

Regards,
Marco

[valentin_kickmaker]

Hello Marco,

Thank you for your reply. I had a hunch that was the case, but I appreciate your confirmation.

Best regards,

Valentin