High-speed low-jitter frequency discrimination phase discriminator and clock data recovery circuit

Abstract

The invention discloses a high-speed low-jitter frequency discrimination phase discriminator and a clock data recovery circuit. The frequency discrimination phase discriminator comprises a Q-channel Bang-Bang-type PD generating a Q-channel signal, an Alexander PD generating an I-channel signal and a tri-state Output FD; the Q-channel Bang-Bang-type PD includes DFF6, DFF7, and DFF8; the Alexander PD includes DFF1, DFF2, DFF3, DFF4, DFF5, XOR1, and XOR2, where DFF1, DFF3, and DFF5 constitute an I-channel Bang-Bang type PD; the three-state output FD includes Latch1, Latch2, and a three-state selector. The Alexander PD in the present invention is additionally provided with two DFFs and two XORs based on the Bang-Bang type PD. The FD consists of the two latches and the three-state selector. ThePFD of the present invention can perform the frequency acquisition function quickly in the frequency discrimination process, and the phase tracking process of the Alexander PD after the frequency lock.

Description

technical field [0001] The invention relates to a high-speed and low-jitter frequency and phase detector and a clock data recovery circuit to improve loop performance, which belongs to the design technology of semiconductor integrated circuits. Background technique [0002] Phase Frequency Detector (PFD for short) detects and judges the input data signal and the clock signal recovered from the loop, and obtains the corresponding output according to the phase relationship between the clock signal and the data signal. It has important applications in phase-locked loops and clock recovery circuits. In integrated circuits, frequency and phase detectors are mainly divided into two categories: one is the PFD based on a periodic signal (clock), and the other is a PFD based on a pseudo-random signal. Of course, since the clock can be regarded as a special data signal, generally clock-based PFD is not suitable for data signals, but data-based PFD can be applied to clock signals, and...

AI Technical Summary

Problems solved by technology

Of course, since the clock can be regarded as a special data signal, generally clock-based PFD is not suitable for data signals, but data-based PFD can be applied to clock signals, and relatively speaking, data-based PFD is more complicated many

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