MONOLITHIC HIGH FREQUENCY VOLTAGE CONTROLLED OSCILLATOR TRIMMING CIRCUIT

摘要

A monolithic high frequency voltage controlled oscillator trimming circuit includes a plurality of capacitance loops (140) selectively connected between a first (120) and second (130) differential input of a voltage oscillator active network (110). A plurality of diodes (159, 160), connected in series with the respective plurality of capacitance loops (140), selectively connect respective capacitance loops (140) between the first (120) and second (130) differential input when forward biased. In a similar fashion, the plurality of diodes (159, 160) selectively disconnect the respective capacitance loops (140) from the first (120) and second (130) differential input when reverse biased. A controller (180) applies a forward biasing voltage to the diode (159, 160) of the selected capacitance loop (140) to connect the capacitance loop (140) to the active network (110) of the voltage controlled oscillator and applies a reverse biasing voltage to the diode (159, 160) of the selected capacitance loop (140) to disconnect the capacitance loop (140) from the active network (110). The diodes (159, 160) used in the capacitance loops (140) form a switch operable at high frequencies and are formed from a bipolar complementary metal oxide semiconductor electro-static discharge protection diode.