Patent ID: 7382362

Claim:
An apparatus, comprising: a detection circuit having: a first input configured to receive a first synch signal at either a first voltage corresponding to first state or a second voltage corresponding to a second state, a first output configured to generate an output signal at either the first voltage corresponding to the first state or the second voltage corresponding to the second state, a first holding circuit configured to hold the first output of the detection circuit at either the first voltage or the second voltage for a predetermined period of time after the first synch signal initially crosses a threshold voltage, the first holding circuit ignoring any subsequent measured transitions of the first synch signal across the threshold voltage during the predetermined period of time; a second input configured to receive a second synch signal at either a first voltage corresponding to first state or a second voltage corresponding to a second state, a second output configured to generate a second output signal at either the first voltage corresponding to the first state or the second voltage corresponding to the second state, and a second holding circuit configured to hold the second output of the detection circuit at either the first voltage or the second voltage for the predetermined period of time after the second synch signal first crosses a second threshold voltage, the second holding circuit ignoring any subsequent measured transitions of the second synch signal across the second threshold voltage during the predetermined period of time.