Compact DAQ数字模块选型求助，5V和5VTTL的区别

[johnabc1234567]

我需要在计算机上读取编码器的输出信号，再通过NI CompactDAQ数字模块输出为0~5V高低电平信号（原编码器输出信号，信号类型为5VTTL单方波，见附图）.我在官网上查找C系列数字模块选型，想请问“数字I/O逻辑电平”这栏，5V和5VTTL有什么区别？我应该选哪种？

[ZYOng]

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@johnabc1234567 wrote:

I need to read the output signal of the encoder on the computer, and then output it as a 0~5V high and low level signal through the NI CompactDAQ digital module (the original encoder output signal, the signal type is 5VTTL single square wave, see the attached picture). I am on the official website I searched for the selection of C series digital modules on the Internet, and would like to ask the column of "digital I/O logic level", what is the difference between 5V and 5VTTL? Which should I choose?

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5V and 5VTTL are essentially the same thing. 

There are a few types of TTL logic. Among them, the most common ones are 5VTTL and LVTTL (3.3V CMOS). See Logic Levels