Phase detecting device and clock data recovery circuit embedded with decision feedback equalizer

Abstract

A phase detecting device and a clock data recovery circuit are provided. The phase detecting device includes a decision feedback equalizer having first and second sample-hold sub-circuits, an edge detector having a third sample-hold sub-circuit, a first XOR gate, and a second XOR gate. The first sample-hold sub-circuit, the second sample-hold sub-circuit and the third sample-hold sub-circuit obtain first sample data, second sample data and transition data, respectively. The first XOR gate executes an XOR operation for the first sample data and the transition data to generate first clock phase shift information. The second XOR gate executes the XOR operation for the second sample data and the transition data to generate second clock phase shift information. Therefore, high-frequency noise disturbance generated from conventional clock data recovery circuit and decision feedback equalizer can be avoided.