I am analog ic designer having 10+ years of experience and I worked on following circuits:
Regulators : LDO, chargepumps, DCDC , OPAMP, Bandgap reference, vbg/R, current mirrors, comparators, under voltage detection, overvoltage detection circuits, oscillators: ring oscillators, relaxation oscillator I/C oscillator, DLL, PLL, SAR ADC.