A grounding key detecting device and method for interference-proof detection of the operation of grounding keys in telephones. A circuit that detects the operation of a grounding key includes a current detection device configured to detect a current flowing when the grounding key is in operation, a comparator configured to compare the detected current with at least one threshold value, and a monitoring circuit configured to detect a first period when the current exceeds the threshold value, detect a second period when the current drops below the threshold value, and output a grounding key detection signal when the first period is greater than the second period.

 
Web www.patentalert.com

< Portable electronic equipment and charger for portable electronic equipment

< Back clip fixture of a receiver and transmitter device

> Portable terminal

> Double-talk and path change detection using a matrix of correlation coefficients

~ 00207