Multi-clock selection switching circuit, clock switching chip and method

Abstract

The invention discloses a multi-clock selection switching circuit, a clock switching chip and a method. The multi-clock selection switching circuit comprises clock gating submodules of which the number is the same as that of clock input signals, only one clock gating submodule is used for allowing to output multiple ways of input clocks, and the other clock gating submodules are all used for forbidding to output the input clocks; the enable end of each clock gating submodule is connected with one logic gate element in a cascaded mode to be used for generating an enable signal for the clock gating submodule; the output ends of all the clock gating submodules are connected to one input end of an or logic gate element of which the number of the input ends is the same as that of the clock input signals; and the output end of the or logic gate element serves as the output end of the multi-clock selection switching circuit.

Description

technical field [0001] The invention belongs to the field of chip circuit design, and in particular relates to a multi-clock selection switching circuit, a clock switching chip and a method. Background technique [0002] At present, the clock switching circuit focuses on how to implement clock switching (mainly switching between two clocks), how to avoid glitches, and use hardware circuits to control the frequency change of the output clock to achieve clock switching. [0003] But these clock switching circuits also have certain problems, which are mainly reflected in: the clock switching circuit is relatively simple, and there are few inventions that can embody multiple advantages in one clock switching circuit, and the stability and reliability of some circuits are also poor. Not high enough. [0004] The invention patent application of the 47th Research Institute of China Electronics Technology Group Corporation with the patent application number "201410754184.0" is "clo...

AI Technical Summary

Problems solved by technology

However, this invention does not clearly point out how to select and switch two or more clocks

[0008] To sum up, in the prior art, there is still no effective solution to technical problems such as single clock switching, glitches in the process of clock switching, and generation of metastable states.

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