A low-power low-voltage current-reused voltage-controlled oscillator with amplitude-balanced technique

A current-reused voltage-controlled oscillator (CRVCO) with amplitude-balanced technique is presented. A cascode cross-coupled pair is adopted, which is used to improve the difference between the differential output amplitudes of CRVCO at a 1.3 V supply voltage. The measured amplitude imbalance ratio is less than 0.15%. The measured phase noise is -114 dBc/Hz at 1MHz offset when oscillation frequency is at 7.8 GHz, resulting in an FOM of - 187dBc/Hz.