Patent ID: 6201450
Filing Date: 2001-03-13
Classification: H03K

Abstract:
An oscillator circuit for generating an oscillating signal of a certain frequency, said oscillator circuit comprising:(a) a capacitance coupled between a first terminal and a second terminal and adapted to have a voltage swing thereacross;(b) a current supply circuit coupled to said capacitance for providing a current through said capacitance, the magnitude of said current being proportional to said frequency and the polarity of said current being reversible;(c) a switching circuit coupled to said current supply circuit and responsive to one or more control signals, for controlling the polarity of said current through said capacitance;(d) a DC shift providing circuit coupled to said capacitance for providing a DC shift value in response to the voltage at said first terminal, the voltage at said second terminal, and a predetermined value; and(e) a control circuit coupled to said capacitance and said DC shift providing circuit for generating said one or more control signals in response to said voltage at said first terminal, said voltage at said second terminal, and said DC shift value so as to maintain the voltage swing across said capacitance substantially constant.