Adjustment of a clock duty cycle

Details Adjustment of a clock duty cycle Adjustment of a clock duty cycle

2002-10-29

2004-12-21

Le, Dinh T. (Department: 2816)

Miscellaneous active electrical nonlinear devices, circuits, and

Signal converting, shaping, or generating

Rectangular or pulse waveform width control

C327S307000, C327S157000, C375S317000

Reexamination Certificate

active

06833743

ABSTRACT:

BACKGROUND
The present disclosure relates to adjustment of a clock duty cycle.
Clock signals may be used in electronic circuits to provide timing information. An important aspect of a clock signal in many applications is the clock duty cycle, which may be defined as the ratio of the time the clock pulse is at a high level to the clock period. For example, a clock signal that is at the high level for one-half of the clock period and the low level for one half the clock period has a 50% duty cycle.
A 50% duty cycle is desirable for many applications. For example, in clock-driven digital systems requiring high speed operation, both the rising and falling edges of the clock signal may be used to increase the total number of operations. Such systems may require a 50% duty cycle to help prevent or reduce jitter and other timing related distortions. In such systems, the duty cycle may be critical to proper performance of the system. Unfortunately, the duty cycle of the clock signal may become distorted or degraded, for example, as a result of semiconductor process errors. Other conditions also may cause the duty cycle to deviate from the desired value. Duty cycle correction circuits may be used to correct or adjust such distortions.


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