Multigigahertz varactorless Si bipolar VCO IC.

A high-performance varactorless VCO is introduced, that uses a capacitively-coupled current amplifier as the active device. The test VCO IC realised in a 2 Mym Si bipolar process exhibits a maximum centre frequency of 2 *5GHz, a time jitter of 2 *5ps at 2 GHz, and temperature coefficient of less than 100 ppm/degree C.