Discriminator and lock phase ring using said discriminator

Abstract

Double edge frequency and phase discriminator includes logic modules of discriminating frequency and phase for rising edge and trailing edge. The said two modules are connected in parallel to constitute the double edge frequency and phase discriminator. Output end of the logic module in double edge frequency and phase discriminator is connected to output logic module. Logic operation is carried out by the output logic module for the output pulse signals from upper half circuit and lower half circuit of logic modules in double edge frequency and phase discriminator in order to generate up / dn signal being in direct proportion to difference of two input signals at both rising edge and trailing edge. The invented discriminator possesses advantages of fast speed, high gain, reducing accumulative phase error, low power consumption and simple structure of circuit.

Description

Technical field: [0001] The invention belongs to the technical field of integrated circuit design, in particular to a frequency and phase detector and a phase-locked loop. Background technique: [0002] Phase-locked loop (Phase Locked Loop-PLL), as the main part of modern clock generator, has become an indispensable module in integrated circuits. With the development of SoC (System-on-Chip) technology and IP core technology, PLL, as a basic IP module, is widely used in wireless communication and microprocessor circuits. Especially the rapid development of the modern communication industry, the emergence of cellular phone (Cell Phone) and Bluetooth technology (Blue Tooth), put forward new requirements for both intra-chip synchronization and inter-chip synchronization. Therefore, the research on the phase-locked loop circuit has attracted more and more people's attention. [0003] The phase-locked loop is an automatic phase-locked loop composed of three basic parts: Phase / Fr...

AI Technical Summary

Problems solved by technology

The traditional trigger-based frequency and phase detector has a large delay, slow working speed, large phase detection dead zone, and takes up a large area; the pre-charged frequency and phase detector works faster, but there is still a phase detection dead zone, and the circuit It is still relatively complicated; nc-level frequency and phase detectors have "no" dead zone, and the circuit structure is relatively simple, but the power consumption is large, the frequency sensitivity is small, and the noise characteristics are poor

These kinds of frequency and phase detectors use a unilateral phase detection mechanism, that is, only output up / dn signals on the rising or falling edge of the input signal, so the phase detection gain is small and the working speed is low.

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