Patent ID: 8076963
Filing Date: 2011-12-13
Classification: H03K,H03L

Abstract:
1. A method comprising: (a) supplying a first signal to a delay line thereby producing a second signal, wherein the first signal has a duty cycle, wherein the second signal is a delayed version of the first signal, and wherein the second signal is delayed a delay time with respect to the first signal; (b) starting to charge a capacitor upon a first edge of the first signal and continuing to charge the capacitor at a first rate until a first edge of the second signal; (c) starting to discharge the capacitor upon the first edge of the second signal and continuing to discharge the capacitor at a second rate until a second edge of the first signal; and (d) controlling the delay time such that an amount the capacitor is charged in (b) is equal to an amount the capacitor is discharged in (c) and such that the delay time is substantially independent of changes in the duty cycle of the first signal.