
Digital Soft Start
Uses Up Counter, DAC and Bus Comparator
- Counter counts PWM clocks
- Maximum count = MAX_COUNT = T_SS*SW_FREQ. For a 1ms SS @ 500kHz, MAX_COUNT = 500
- Need 10 bits = max SS ramp time = 1023/SW_FREQ = 2.046ms
- DAC LSB = 1mV, Max Vss = 600mV
- Therefore we need to scale DAC output with VCVS