5.14 Overcurrent Protection

The MCP16367/8/9 features instantaneous cycle-by-cycle current limit by sensing the current through the high-side switch.

A leading edge blanking is provided on the high-side switch to prevent falsely triggering the overcurrent limit.

The device also offers frequency fold-back and overcurrent protection that inhibits future pulses for prolonged overloads or short-circuit condition.

If there are prolonged overloads at high input voltages and the overcurrent protection is tripped, the next three switching pulses will be inhibited such that the inductor current is allowed to decrease to lower values.

At the same time, if the feedback voltage decreases, the switching frequency will also decrease down to 200 kHz.