180XFAB_DCDC_05 is capable to generate -4.2V ÷ -3.3V (-3.7V typical value) voltage and can maintain 50uA load for -3.7V output. The block consists of OTA and transistor-capacitive multiplier cells. The DC/DC is used for forming negative supply. Upon power-up to typical 3.7V voltage at the fully charged 100nF output capacitor connected, slew rate of output voltage will be limited of the internal frequency correction circuits and is approximately 4.3 V/us. Start-up time is increased with increasing capacitor nominal value proportionally.