A Performance Comparision of OTA BasedVCO and Telescopic OTA Based VCO forPLL in 0.18um CMOS Process

This paper describes a performance comparison of two Voltage Controlled Oscillator for Phase Locked Loop. OTA Based VCO and Telescopic OTA Based VCO for PLLs in a 0.18 μm digital CMOS process are designed and their performances are compared based on the measurement results. Measured performances shows that jitter and power consumption in Telescopic OTA Based VCO is reduced as compared to OTA Based VCO with wide frequency range. These designs are suitable to design low power and low jitter Phase locked loop.