Stable voltage controlled oscillator

摘要

A voltage controlled oscillator (VCO) is stabilized against variations in output frequency resulting from changes in temperature or the power supply voltage by trimming the voltage controlled oscillator from a second master VCO which is connected into a phase lock loop. Each of the two voltage controlled oscillators has an output frequency which is a function of two inputs. The signal input to one control input of each of the VCO's is the output of the low pass filter in the phase lock loop. The VCO's may both be implemented by cross-coupled NOR gates with grounded capacitor inputs.