摘要 |
A Voltage Controlled Oscillator circuit has a resonant tank circuit 130 and a differential pair of transistors 110, 120 coupled to drive the tank circuit. A differential cascode pair 140, 150 is provided, coupled between the differential pair and the tank circuit. A differential feedback path is also provided, which is cross-coupled from the tank circuit to drive the differential pair. Base terminals of the cascode pair are AC cross-coupled with respect to the differential pair such that AC base currents of the differential pair and the cascode pair are cross-compensated. This is said to improve noise performance. |