Unity Gain Buffer with Op-Amp 741 for LVDT Sensor

[Ramana]

Hello,

Here need a suggestion on Unity gain buffer using op-amp 741.

The output i need in the range according to change in LVDT sensor (resistive type).
The output of the sensor is 35mv to 3.5 VDC.
The circuit i build using op-amp741 as voltage follower where the output is given feedback to non-inverting input.
Now the output from Op-amp am getting is 1.85 VDC to 3.5VDC.

The required output is according to the change in LVDT sensor(resistive type) i.e from some mV to 3.5 VDC.
How can i minimize the voltage of 1.85 VDC at the op-amp ouptut?

Best Regards.

 

[davenn]

if you are not running the op-amp off a split rail supply, you won't get the output below ~ 2V

as an aside, why are you using such an old op-amp ? there are many better newer devices

Dave

 

[Ramana]

Thank you for yur reply Dave.

op-amp off a split rail supply

I don't understand split rail supply.

I don't have any other components than Op-Amp right now.

 

[Ramana]

Ok. Is there any circuit for making split voltage (negative voltage)??

 

[davenn]

OK here's one example of a split rail PSU

depending on your overall circuit, you may be able to use a +5V 0V -5V supply

NOTE ... I don't know where your are in the world, nor your mains voltage, use the appropriate transformer. Also if you only need a + and - 5V the transformer output could also be lower say 9-0-9VAC

Dave

 

[zoki85]

Ok. Is there any circuit for making split voltage (negative voltage)??

Yes, a resistive voltage divider being the simplest one.

 

[davenn]

Yes, a resistive voltage divider being the simplest one.

as long as the overall circuit current requirements are very low, that's OK

since we don't know the full extent of what the OP is doing, I didn't suggest that method

Dave

 

[jim hardy]

Two batteries can make a split supply.

LM324 can work from a single (not split) supply .

 

[Ramana]

Thank you dear all for your best suggestions.

I have used CENTER-TAPPED BATTERY CIRCUIT for split rail voltages for Op-Amp 741.
The output is exactly as what i needed. That changes according to LVDT sensor.

Best Luck.