A generation circuit and a control method of a digital oscilloscope reference clock

Abstract

The invention discloses a generation circuit and a control method of a reference clock of a digital oscilloscope. The generating circuit comprises a 10MHz reference clock generating circuit, an input / output selection control circuit and a parallel circuit of the functional circuit boards in the oscilloscope and the generating circuit. The input and output selection control circuit comprises an FPGA control and input and output selection circuit 1 and a reference clock input / output selection circuit 2, the FPGA is controlled to output different control bits through a human-computer interactioninterface; the external output of a 10MHz reference clock, the reference clock input of each function board in the oscilloscope and the input of an external reference clock are realized in one channel. In the whole process, a user only needs to select a 10MHz reference clock as a reference input or a reference output on a human-computer interaction interface, so that the practicability and the convenience of the oscilloscope are improved, and the functions of the oscilloscope are enriched.

Description

technical field [0001] The invention belongs to the technical field of testing, and in particular relates to a generation circuit and a control method of a reference clock of a digital oscilloscope, which is applied to an internal 10MHz reference clock of a digital oscilloscope, and can complete the input of an external reference clock and output it as a reference clock externally and to each of the internal oscilloscopes. The reference clock input of the function board realizes the input and output of the 10MHz reference clock on one channel. Background technique [0002] 10MHz is a commonly used frequency band in the test field, and a reference clock of this frequency is required in the internal circuit of the oscilloscope and other test circuits to achieve signal time base matching. The stability and accuracy of the reference clock will have a great impact on the test results, resulting in wrong test results. Moreover, when testing the 10MHz internal function board of th...

AI Technical Summary

Problems solved by technology

One is to generate a reference clock through a hardware circuit on the function board and send it to other function boards through a connector to meet the internal requirements of the oscilloscope for a 10MHz reference clock, but it cannot simultaneously provide a stable and accurate 10MHz reference clock to the outside; the other is Place reference clock generation circuits on different functional boards inside the oscilloscope. Although the reference clock requirements of each functional board can be realized, when different functional boards interact, additional circuits need to be designed to match the reference clock, which increases the difficulty of debugging.

However, neither of the above two methods can satisfy the observation of an externally input 10MHz reference clock in the same hardware circuit at the same time.

[0004] That is to say, although the existing technical solutions can realize the generation and transmission of the 10MHz reference clock, they cannot simply and efficiently realize the input of the external 10MHz reference clock, the output of the internal 10MHz reference clock, and the clock input to different functional boards inside the oscilloscope. and other functions

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