VOLTAGE CONTROLED OSCILLATOR FOR FREQUENCY BAND PASS

摘要

The voltage controlled oscillator (VCO) triggers certain frequency band between two reference voltage levels. The VCO comprises a voltage divider (10) for distributing the input voltage (VDD) by connecting three FETs in series, a comparator (20) having two operational amplifiers (OP1,OP2) for comparing the two voltage levels of the voltage divider with capacitor voltage, an output voltage controller (30) having an output transistor (M4) and a drive transistor (MS) to control the output voltage of the oscillator according to the output signal of the comparator (20), and a wave shaping unit (40) for shaping the wave form of oscillator output signal and applying the signal to a capacitor (C).