一种数字示波器快速自动设置方法研究

Research on Fast Autoset Function of DSO

使用数字示波器进行未知幅度和频率的波形测量时,手动调节常需要多次改变幅度档和时基档以获得理想的显示。为了使测量更加方便,数字示波器提供了自动设置的功能。目前在实现自动设置时通常采用基于采样数据参数测量的方式获取信号的幅度,并利用模拟电路获取信号的频率。但这种方法一方面运行速度较慢、另一方面幅度测量和频率测量互相影响,造成常需要多次运行自动设置才能获得理想的显示。该文提出一种完全基于硬件的新型自动设置的控制方法,通过利用数字逻辑电路分别进行幅度与频率的测量,使自动设置的速度与准确度都得到极大的提升,大大提高了示波器在测试中的应用能力。

When measuring the amplitude and frequency of an unknown signal with digital storage oscilloscope(DSO),vertical sensitivity and horizontal sensitivity need to be changed manually for several times to acquire an ideal display result.In order to simplify this manual operation,autoset function is provided in DSO.The existing autoset functions generally use sample data parameter measurement function to get the signal amplitude,and acquire signal frequency by analog circuit.The problem of this method is that the speed of autoset is limited on one hand.On the other hand,amplitude and frequency measurement are interaction,which results in several times of utilizing autoset function to show the desired display result.A new complete hardware based control method of autoset function is put forward in this paper.By measuring signal amplitude and frequency separately with digital logic circuit,the speed and accuracy of autoset function are greatly improvement,which increases the application ability of DSO in real tests.