1-5 GHz duty-cycle corrector circuit with wide correction range and high precision

An all-analogue feedback duty-cycle corrector (DCC) circuit with high precision and frequency is presented to tighten duty cycle into an allowable range and compensate for duty-cycle uncertainties in high-speed interfaces. The proposed DCC is employed to calibrate the duty cycle of the clock to reduce the deterministic jitter introduced by the duty-cycle distortion. It extracts the duty-cycle information by a differential duty amplifier detection scheme and corrects the clock distortion by a duty-cycle adjuster through the negative feedback loop. The DCC has improved robustness, correction range and operating frequency as compared with other DCCs. With post-simulated results using 55 nm CMOS technology, the output duty cycle is corrected to 50 ± 0.1% over the input duty-cycle range of 20-80% for 1-5 GHz. It consumes 3.6 mW at 3 GHz using a 1.2 V supply voltage and occupies an area of only 0.00174 mm².