A time-based analog-to-digital converter using a multi-phase voltage controlled oscillator

摘要

A time-based analog-to-digital converter(ADC) employing a multi-phase voltage-controlled oscillator(VCO) is presented. The VCO is based on a ring oscillator which converts analog input voltage to phase information. Digital output is produced by a phase quantizer which consists of a counter for coarse quantization and phase detector for fine quantization. Using this technique, an 8-bit 100Msamples/s ADC is designed and simulated. Impact of jitter and VCO linearity on the ADC performance is analyzed and verified.