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?
