A Tunable Waveform Generator with Wide Tuning Range for Instrumentation Applications

Abstract

Different types of Tunable Waveform Generators with Wide Tuning Range for Instrumentation Applications have been delineated herein. Each waveform generator consists of a hysteresis Schmitt trigger and a timing circuit which works as integrator. A wide frequency tuning range can be obtained by using these waveform generators. Along with the waveform generators, frequency divider (FD) circuit and path selector stages also been designed here to generate lower band of frequencies. This lower band of frequencies is used in various biomedical applications. Wave form generators, frequency divider (FD) circuit and path selector stages have been designed using UMC 180 nm CMOS process technology.
First type of waveform generator has been designed with a dual supply of ±1.8 V for the oscillator. Bias resistances of values 10 k? 15 k? and a load capacitance of 10 pF were used to generate a nominal frequency of 17 kHz with peak-to-peak amplitude (Vp-p) of 3.2 V. One of the important features of waveform generator is that amplitude and frequency can be tuned linearly and independently. Other proposed waveform generators have been designed using single supply of +1.8 V.