Hi, I have a difficulty understanding differential delay cell used in oscillators. Compared to single-ended digital delay cell (the inverter), it is mentioned in books that differential delay cells gives mostly sinwave outputs instead of pulse outputs (). So, how is this sinwave outputs used as clock signals? Doesn't clock signals needs pulse-like outputs with sharp rise and fall edges? I was wondering whether a comparator is placed after the differential delay cell based oscillator to make the output more pulse-like? Thanks.