SLLSEK2A June 2014 – March 2017 DRV8846
PRODUCTION DATA.
An analog current limit circuit on each FET limits the current through the FET by limiting the gate drive. If this analog current limit persists for longer than the OCP deglitch time tOCP, all FETs in the H-bridge are disabled and the nFAULT pin is driven low. The device remains disabled until the retry time, tRETRY, occurs. The OCP is independent for each H-bridge.
Overcurrent conditions are detected independently on both high-side and low-side devices; that is, a short to ground, supply, or across the motor winding all result in an OCP event. Note that OCP does not use the current sense circuitry used for PWM current control, so OCP functions without the presence of the xISEN resistors.