Novel Approximate Square-Root Domain All-Pass Filter with Application to Multiphase Oscillators

Abstract

A novel approximate square-root domain all-pass filter operating from a single 3.3 V supply is reported. The circuit requires a small number of transistors, with a bandwidth exceeding 100 MHz. Two-phase and three-phase oscillators based on cascaded sections of the proposed filter are constructed followed by a generic multiphase oscillator. Simulation results, using AMS 0.35 ? BiCMOS technology parameters, and experimental results are given.