Passive crystal oscillator sharing circuit

Abstract

The invention provides a passive crystal oscillator sharing circuit, which comprises a crystal oscillator circuit and a system-on-chip. The crystal oscillator circuit is used for outputting a clock signal. The crystal oscillator input pin and the crystal oscillator output pin of the system-on-chip are both connected with the crystal oscillator circuit and used for receiving clock signals and thenoutputting the clock signals. The crystal oscillator input pin of the integrated chip is selectively connected with one of the crystal oscillator input pin and the crystal oscillator output pin of thesystem-on-chip through the passive filter so as to receive a clock signal output by the system-on-chip. The passive filter reduces the interference, enables the frequencies of the clock signals of the system-on-chip and the integrated chip to be consistent, and reduces the number of crystal oscillators.

Description

Technical field [0001] The present invention relates to the technical field of circuits, in particular to a passive crystal oscillator sharing circuit. Background technique [0002] In a circuit board with multiple chips, in order to ensure the accuracy and reliability of the information transmission between each chip, each chip needs a special crystal oscillator to provide the same frequency clock signal, so each chip in the current technology Both need to set up an independent crystal oscillator, which leads to increased costs. [0003] In order to solve the above problems, the prior art provides a 24M universal crystal oscillator circuit, such as figure 1 As shown, that is, two or more chips share an active crystal oscillator, and through the strong driving ability of the active crystal oscillator, multiple chips share an active crystal oscillator. However, the above technical solution uses a higher cost active crystal oscillator. Therefore, the processing cost and material cos...

AI Technical Summary

Problems solved by technology

[0002] In a circuit board with multiple chips, in order to ensure the accuracy and reliability of information transmission between each chip, each chip needs a dedicated crystal oscillator to provide the same frequency clock signal, so each chip in the current technology Both need to set an independent crystal oscillator, resulting in an increase in cost

[0003] In order to solve the above problems, a 24M general-purpose crystal oscillator circuit is provided in the prior art, such as figure 1 As shown, more than two chips share one active crystal oscillator, and multiple chips share one active crystal oscillator through the strong driving capability of the active crystal oscillator. However, the above technical solution uses a relatively high-cost active crystal oscillator. Therefore the processing cost of prior art and material cost are higher

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