6.7

Overvoltage protection

The overvoltage protection monitors the FB pin and enables the low-side MOSFET to discharge the output

capacitor if the output voltage is 20% over the nominal value.

This is a second-level protection, and it should never be triggered in normal operating conditions if the system is

properly dimensioned. In other words, the selection of the external power components and the dynamic

performance determined by the compensation network should ensure an output voltage regulation within the

overvoltage threshold even during the worst-case scenario in terms of load transitions.

The protection is reliable and able to operate even during normal load transitions for a system whose dynamic

performance is not in line with the load dynamic request. Consequently, the output voltage regulation would be

affected.

The DCP3601 device implements a negative current limitation (IVY_SINK, refer to Table 7) to limit the maximum

reversed switch current during the overvoltage operation.

6.8

Thermal shutdown

The shutdown block disables the switching activity if the junction temperature is higher than a fixed internal

threshold (TSH, refer to Table 7). The thermal sensing element is close to the power elements, ensuring fast and

accurate temperature detection. A hysteresis of approximately 20 °C prevents the device from turning ON and

OFF too fast. After a thermal protection event has expired, the DCP3601 restarts with a new soft-start.

DCP3601

Functional description

DS14782 - Rev 1

page 10/26