Method and apparatus for measuring data timing using unity time-voltage sawtooth ramps

摘要

A method and apparatus for converting skew in a received signal to a low frequency voltage. A signal is received at a destination node from an original signal from a source node. A unity time-voltage sawtooth ramp signal is created at the destination node. The amplitude of the unity time-voltage sawtooth ramp signal is a value in voltage proportional to a pulse width value of the original signal. The unity time-voltage sawtooth ramp signal starts just before the start of the received signal. A skew time is measured from the start of the unity time-voltage sawtooth ramp signal to a threshold level on an edge of the received signal. The measured skew time is correlated to a voltage level on the unity time-voltage sawtooth ramp. The measured skew time for each edge is converted into a pulse where the voltage level of each pulse being proportional to the measured skew.