Actually I'm converting RTD resistance into 4to20 ma current and output of bridged & instrumentation amplifier is 3.7 to 4.7 volts so I need 1 to 5 that can easily converted into 4-20maWhat supply voltages do you have?
What is the output load?
How accurate does the shift need to be?
V1 is a fixed offset of 4.600V. Note that this must be very precise. A 1mV error causes a 3mV error at the output. Watch it if it is a trim pot off +15V.
May I suggest using fixed resistors to make a trim pot work in a small range of voltages. That's one way to get a more accurate voltage setting.this must be very precise.
Yeah, but if the 5V supply drifts from 5.000 to 5.050 (1% change), the output of the scaling opamp shifts 3%, i.e., it is ratiometric. In the OP's case, he is likely trying to get 4.600V from his +15V supply. How stable is that?May I suggest using fixed resistors to make a trim pot work in a small range of voltages. That's one way to get a more accurate voltage setting.
For instance, if you're trying to get 4.6V out of a 5V supply, put a 4.7 k resistor under a 1 k pot. That way the pot works from 4.1 volt to 5 volts.
Hi now my inputs is changed to 3.2 to 4.8 into 1-5volts so if I use your calculations than I'm getting some variation about 1 volt can you fix it?
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