Patent ID: 7061295
Filing Date: 2006-06-13
Classification: G11C,H02M

Abstract:
1. A ring oscillator comprising: a plurality of first inverters coupled in series with an output of one first inverter coupled to the input of another first inverter to form a ring, each of said plurality of inverters providing a first inverted signal having characteristics dependent on an applied first bias current, one of said first inverters providing a first clock signal; a plurality of first capacitors, each of said plurality of first capacitors being coupled to the output of a respective one of said plurality of first inverters; a second inverter having an input coupled to the output of said one of said plurality of first inverter providing said first clock signal and having an output for providing a second clock signal having characteristics dependent on an applied second bias current, the ratio of first bias current to the second bias current being such to adjust the phase between the first and second clock signals to a pre-selected value; and a second capacitor coupled to the output of the second inverter, the capacitance of each of the plurality of first capacitors being equal to the capacitance of the second capacitor.