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UCC28C42: Soft Start Implementation - how big does the capacitor can be?

Part Number: UCC28C42

Hi Everyone,

The datasheet of the UCCx8C4x gives a way to impliment soft start:

The diode is there to "forces a soft-start period each time the PWM goes through UVLO condition that forces VREF to go low. Without the diode, the capacitor remains charged during a brief loss of supply or brown-out, and the device does not enable a soft-start function upon re-application of VDD."

If VREF go low very fast the current into the pin will be very high (as per I = Css * dV/dt) - the datasheet does not state the maximum current into the VREF pin.

Is there any guidelines regarding the size of the capacitor? maybe a series resistance with the diode is recommended to not damage the chip?