Patent ID: 6049234
Filing Date: 2000-04-11
Classification: H04M

Abstract:
The edge detection circuit which detects an edge which is one of a rise and a fall in an input voltage changing with a top peak voltage and a bottom peak voltage lying and outputs a current denoting detection of the edge, the edge detection circuit comprising:first voltage determination means for determining a first specific voltage laid between the top peak voltage and the bottom peak voltage;second voltage determination means for determining a second specific voltage laid between the top peak voltage and the bottom peak voltage;first transition detection means for detecting a first transition of the input voltage at the first specific voltage;current permission means for permitting the current to flow upon detection of the first transition;second transition detection means for detecting a second transition of the input voltage at the second specific voltage; andcurrent forbidding means for forbidding the current to flow upon detection of the second transition.