I am trying to measure an RTD's (PT1000) resistance via the following circuit. Everything seems to be stable voltage wise, from the -IN pin, +IN pin, vref pin, vcc.
However, when i touch the RTD's wire (plastic part) lightly by hand, the output from the AD623 is erratic, changing up to 200mV while i touch it. Only the output, all other pins are stable when i touch the RTD. For example +IN pin is 1.6V (stable) and -IN pin is 1.55V (stable).
Any ideas for solving this issue?
thanks
However, when i touch the RTD's wire (plastic part) lightly by hand, the output from the AD623 is erratic, changing up to 200mV while i touch it. Only the output, all other pins are stable when i touch the RTD. For example +IN pin is 1.6V (stable) and -IN pin is 1.55V (stable).
Any ideas for solving this issue?
thanks
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