High precision yet wide range on-chip oscillator with dual charge-discharge technique

Abstract

This paper describes a high precision all digital on-chip oscillator. This architecture can achieve absolute precisions beyond 0.1% with only one trim. Once trimmed, the oscillator can produce any frequency within the programmable range with similar accuracy. If there are multiple oscillators on same die, trimming one oscillator will be sufficient to trim all the oscillators at multiple frequencies. The designed prototype achieved better than 0.17% accuracy with a 112MHz clock consuming 250uA. The area for the oscillator is just 0.02mm2. Keywords: Precision Oscillator, High accuracy oscillator