# Analog input on OP7200

**URL:** <https://forums.digi.com/t/analog-input-on-op7200/19908>\
**Category:** Rabbit Software\
**Tags:** op7200\
**Created:** [October 5, 2018, 2:00pm UTC](https://forums.digi.com/t/analog-input-on-op7200/19908 "2018-10-05T14:00:44Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Rett](https://avatars.discourse-cdn.com/v4/letter/r/65b543/32.png) [@Rett](https://forums.digi.com/u/Rett)\
**Post date:** [October 5, 2018, 2:00pm UTC](https://forums.digi.com/t/analog-input-on-op7200/19908/1 "2018-10-05T14:00:44Z")

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Hi,

Please help me to solve this problem.

I use OP7200 to input analog signal, but the voltage is not correct.

Will be more 0.060v when plug wire in, although no signal.

So, I try to use “adrd\_se\_ch.c” to check voltage for analog Pin that no wire plug in.

All have value from 0.020v to 0.025v… I think it must be Zero, since no signal in.

Please help & give me an advice.

Thanks.

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<div class="post-metadata">

**Author:** ![TomCollins](https://sea2.discourse-cdn.com/flex016/user_avatar/forums.digi.com/tomcollins/32/37_2.png) [@TomCollins](https://forums.digi.com/u/TomCollins)\
**Post date:** [November 29, 2018, 5:29pm UTC](https://forums.digi.com/t/analog-input-on-op7200/19908/2 "2018-11-29T17:29:19Z")

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You might need to recalibrate your inputs to get a reading closer to 0, or update your code to consider voltages below some threshold as equivalent to 0.

What happens if you check that pin with a volt meter compared to the analog ground?