a frequency coincidence detection circuit for detecting frequency edges for each of a plurality of periodic digital signals . the circuit generates count indicators for each of the periodic digital signals and compares each of the count indicators to a programmable sensitivity input to determine a coincidence window for the corresponding one of each of the periodic digital signals . the circuit determines a signal coincidence of the coincidence windows . in another embodiment , a frequency coincidence detection method is provided . the method detects frequency edges for each of a plurality of periodic digital signals , generates count indicators for each of the periodic digital signals and compares each of the count indicators to a programmable sensitivity input to determine a coincidence window for the corresponding one of each of the periodic digital signals . the method determines a signal coincidence of the coincidence windows .