A temperature-compensated CMOS clock oscillator

摘要

A monolithic temperature-compensated clock oscillator circuit may be implemented in a conventional CMOS IC fabrication process by use of a combination of positive and negative temperature coefficient resistors 101 to set the current driving a relaxation oscillator 100. The temperature coefficients of the oscillator 100 and the driving current substantially cancel to provide a very low temperature coefficient. The positive tempco resistors may be poly resistors, silicon resistors or nwell resistors. The negative tempco resistors may be of high-poly type. No external resistors are required. The oscillator frequency may be programmable. The negative and positive temperature coefficient arrays may be placed in parallel or in series (figure 6).