Patent ID: 6054904
Filing Date: 2000-04-25
Classification: H03K,H03L

Abstract:
A voltage controlled oscillator comprising:an odd number of inverter circuits connected in a ring; anda current control circuit for generating and outputting a control voltage supplied to said inverter circuits, wherein each of said inverter circuits comprises:a first current source transistor connected to a first power source;a second current source transistor connected to a second power source;a complementary transistor circuit connected between said first current source transistor and said second current source transistor;a current discharge preventing circuit for preventing discharging of electrical charge accumulated in a parasitic capacitance, said current discharge preventing circuit being connected between said first power source and a connection node of said second current source transistor and said complementary transistor circuit; anda current charge preventing circuit for preventing charging of a parasitic capacitance, said current charge preventing circuit being connected between said second power source and a connection node of said first current source transistor and said complementary transistor circuit, wherein said current control circuit outputs the control voltage to said first current source transistor and said second current source transistor in each of said inverter circuits.