# How much Volts one digital pin supports?

Hello,

I have some sensor,output is 1±0.15mV

Can Arduino uno support that or I need some resistor or Amplifier

Thanks for your time

You need an amplifier. The standard 5V Arduino digital inputs accept 0 to 5V.

thank you i really appreciate it

For inputs to be detected as HIGH they must be at least 0.6 Vcc and assuming Vcc = 5v then that works out as 3v

The most useful thing is for you to post a link to the datasheet for your sensor and then we can give more useful advice.

...R

If it's a digital signal, you could run it thru a comparator (like the LM358 on the Arduino board), comparing the signal to say 1mV and letting the comparator make a high output for the Arduino when the signal is above that, and low for below that.

If it's an analog signal, then an op amp can be used to offset the signal to 2.5V and amplify the signal to close to 0-5V range for an ADC input to read it.
http://masteringelectronicsdesign.com/the-transfer-function-of-the-summing-amplifier-with-n-input-signals/
Put your signal into V1, set the gain to 1000, set V2 to .002V so the output is then 2V +/-1.5V if I got the math right.

Gain of 1000 might be noisy, perhaps do a gain of 10 and then another of 100.

If it is an analog signal you could use the internal 1V1 reference and wouldn't need any amplification.

I understand OP wants to read an analogue voltage between 0.85mV and 1.15mV.
You definately need a preamp for that.

I would like to see more info about this sensor before giving any advice.
Leo..

Yes, need spec sheet. I recommend only after I see the spec sheet.