I am trying to design a circuit to read pressure with a voltmeter. I have a
pressure transducer that has an output of .53 volts at 0 psi to 4.53 volts at
500 psi. I used Ltspice to test my circuit and it works fine with the
simulation. The problem is when I build the actual circuit, the output is not
correct. Any input between 1 and 4.53 volts will give me the correct
output,(within 1 to 2 psi which is close enough for my use). The problem is
in the range between .53 and 1 volt. This is the range I would like it to be
the most accurate. At .53 volts input, the output reads .14 volts and should
read 0 volts. As I increase the voltage to 1 volt, the error gradualy
decreases. I am useing a 741 opamp with a dual-polarity supply from two 9
volt batteries. Would a different opamp help? Please note that I am a novice.
pressure transducer that has an output of .53 volts at 0 psi to 4.53 volts at
500 psi. I used Ltspice to test my circuit and it works fine with the
simulation. The problem is when I build the actual circuit, the output is not
correct. Any input between 1 and 4.53 volts will give me the correct
output,(within 1 to 2 psi which is close enough for my use). The problem is
in the range between .53 and 1 volt. This is the range I would like it to be
the most accurate. At .53 volts input, the output reads .14 volts and should
read 0 volts. As I increase the voltage to 1 volt, the error gradualy
decreases. I am useing a 741 opamp with a dual-polarity supply from two 9
volt batteries. Would a different opamp help? Please note that I am a novice.