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What are some typical output parameters of sensors that have resistance output or current output?

For voltage output, typical sensors can give some milivolts or 5V or 10V. etc.

For current one typical is 4-20 mA. For resistance for example 10 KOhm (like NTC thermistor).
But what are some other typical values for current- and resistance-output sensors?

The reason for asking this is that I'm going to make some simple universal board for connecting sensors and I wonder what input ranges I should support.

zupazt3
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    See this X-Post https://electronics.stackexchange.com/a/339863/139766 – Trevor_G Dec 03 '17 at 15:10
  • @Trevor I don't see how this is related? – zupazt3 Dec 03 '17 at 15:56
  • @zupazt3 There's op-amps for this. – Harry Svensson Dec 03 '17 at 16:13
  • Op-amp? Are you both sure you read my question? :) I am already using op-amp as a buffer and voltage divider but this is completely not what I am asking. I am asking what are the typical output current / resistance of sensors, because I need to choose some resistors for shunt resistors (for current measurement) or to set current source's current (for resistance measurement). But I am not sure what kind of current range and resistance range to choose as a most universal one. – zupazt3 Dec 03 '17 at 16:21
  • @zupazt3 I was talking about your last paragraph. This comment you've written is information I can't find in your question "*I am already using op-amp as buffer*". So yes, I have read your question, but not your mind. Because I'm not a mind reader. I'm just a level 5 warlock. – Harry Svensson Dec 03 '17 at 17:25
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    It's related in that there is no one answer fits all a generic input device. It is better to make it modular so you can adapt to suit the needs at hand. – Trevor_G Dec 03 '17 at 17:58

1 Answers1

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There is no universal answer.

There is no one set of resolution, bandwidth, and range that works for all sensors. This is because in any real system, each of these parameters trade off against the others. No matter what you pick, there will be some sensors that require more resolution, perhaps because the resolution you do have is spread out over a too large range, require more bandwidth than what you picked, or have a larger range than what you picked.

For example, to handle a microphone you might want 16 bits over ±5 mV at 20 kHz. However, to support a 0-15 V sensor in a car, for example, you'd need another 11 bits to still maintain the 16 bit resolution for the microphone. Now you need 27 bits at 20 kHz. Then what happens when you want to digitize video? Something using the full power line voltage range?

Some sensors produce a voltage. Others a current. Others look like variable resistors.

Your concept is simply not realizable.

Fageddaboutit.

Olin Lathrop
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  • But I'm not assuming to build a board for ALL sensors. Just some most popular. I already gave you an example: 10 KOhm is pretty popular for resistance. 4-20 mA is also some standard for current. Now what I'm asking is not "universal answer" but most **typical** values of sensors, for simple cases. Of course there will be some more advanced sensors requiring specific sig. conditioning. I'm interested in sensors for temperature, humidity, air pressure, light, Hall effect, pH of soil etc etc. those kind of things. Not a microphone or video. – zupazt3 Dec 03 '17 at 15:54
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    But that's not what you asked: *"I'm going to make some simple **universal** board for connecting sensors"*. – Olin Lathrop Dec 03 '17 at 17:50
  • @zupazt3 Have you read your own question? – Harry Svensson Dec 03 '17 at 18:22