A 10-bit fast lock data recovery compensating pulse-width distortion for isolated data communications

This paper presents a fast lock data recovery, which can compensate pulse-width distortion of the data signal waveform caused by the optocoupler. The proposed technique exploits the nature that only the rising edges of the data have a fixed amount of time delay at the output of the optocoupler. This delay is cancelled out by a recursive digital calculation after the bit number estimation using the blind oversampling. An experimental prototype fabricated in an in-house 40-V 0.8-um SOI BCD automotive process compensates more than ±50% pulse-width distortion with only 10-bit training as a preamble pattern. It can be applied with an inaccurate CR oscillator with 0.17-UI (unit interval) peak-to-peak jitter and up to ±10% frequency offset between the transmitter and the receiver.