Voltage controlled oscillator circuit using AO

This voltage controlled oscillator circuit is designed using LM111 voltage comparator and LM101 operational amplifier and some other electronic components.
Voltage-controlled oscillator circuit is an oscillator that its frequency is controlled using a voltage signal.
The VCO described here provide both triangular and square wave output. The control voltage can be varied between 5 mV to 5 V, to produce oscillation frequency from 10 Hz to 10 KHz.