A high speed, high linearity voltage-to-time converter

Abstract

In this report, a signal processing methodology named time-mode signal pro- cessing is proposed. In an time-mode analog-to-digital converter (ADC), time- difference variable is used as an intermediate signal between the analog input and its digital output. One of the most significant component in time-mode ADC is the analog-to-time converter(ATC). It converts the analog input to a corre- sponding time signal. In this project, four different approaches are achieved. The general idea to convert voltage to time is continuously comparing the input volt- age with a ramp voltage which increases linearly with respect to time. The ATC circuit should convert the analog input voltage signal to time signal with high linearity, high speed and low power. All the designed ATC circuits are described in transistor level schematic and their performances are simulated with Cadence. The integrated circuits (IC) were designed with 0.18μm CMOS technology.