Patent ID: 7642767

Claim:
A duty cycle measuring device, comprising: a logic device, coupled to an input signal, outputting a sampled input signal in response to a non-coherent sampling clock signal, the non-coherent sampling clock signal frequency being different than the input signal frequency, the non-coherent sampling clock signal being generated by an irregular sampling oscillator having a randomly varying frequency; a counter, which counts the number of times the sampled input signal has a predetermined logic value in response to the non-coherent sampling clock signal, wherein an input of the counter is coupled to the output of the logic element, and a clock input of the said counter is coupled to the non-coherent sampling signal; a pulse counter that counts the number of times the input signal is sampled, wherein an input of the pulse counter is coupled to the non-coherent sampling signal, and a processor that provides the duty cycle of the input signal in response to a counter output and a pulse counter output.