Fully differential voltage controlled oscillator (VCO) providing precise clock signal for digital and analog integrated circuits, e.g. transceivers with low jitter at low supply voltage, with bistable flip-flop, etc.

摘要

The bistable flip-flop has set and reset input and inverting and non-inverting output forming VCO outputs. There are two capacitors and fully differential comparator, comparing voltage over first capacitor with applied differential trim voltage, with its output coupled to set of bistable flip-flop. Second fully differential comparator compares voltage over second capacitor with differential trim voltage and its output is coupled to reset input of flip-flop. Several switches are coupled to output of flip-flop and affect capacitors for their (dis)charging according flip-flop state.