Voltage -/+3 in +/-10 out

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Make it like this. Add a 1k resistor in series with the 18k resistor then the output will be +9.95V.
 

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Ron I am not conerned about the offset at the moment because the first problem is getting the amp working
paul
 
audioguru said:
Make it like this. Add a 1k resistor in series with the 18k resistor then the output will be +9.95V.


you circuit shows a minimum load of 2 k I am only connecting a volt meter to the output
 
Your opamp or your meter is not working properly.
Maybe you have unshielded cable at the input that picks up mains hum.
 
Do you have a part number, or better yet, a datasheet for your sensor that we can look at?
 
Wait... the IDG300 is rated for single supply operation, with Vdd=3 V and a static output of Vdd/2 = 1.5 V. You won't get a negative voltage out of it.
 
The voltage can swing from 0.05 V to Vdd-0.05 V and the zero-rate voltage is 1.5 V (with Vdd=3 V).
If you're monitoring two axes, choose a dual single-supply op amp, with low offset. Why are you going to amplify the output of the sensor?
 
Can you recommend an op amp I would like to have 2.5 volt as my static, and + 5volt to zero as my swing. I have an input on my servo amplifier that can accept that voltage.
I just tried it on the sensor with no amp and it does work but with a slower response. I will also need to have a fine tune to stop the motor creaping
 
The most straight-forward way to do that is to use a level shifter (+1.5 V) with an amplification of 2. Google for "level shifter op amp". Be aware that you may introduce significant error if resistors are not matched.
 
eng1 said:
The most straight-forward way to do that is to use a level shifter (+1.5 V) with an amplification of 2. Google for "level shifter op amp". Be aware that you may introduce significant error if resistors are not matched.
No, all he needs is a gain of 2.5/1.5. The gain will also do the level shifting.
 
paul200 said:
Thank you!!
You can use the same circuit you were using before. Make the feedback resistor 10k, and the resistor to GND 15k. You could use a 5V, single-supply, rail-to rail output op amp, or you could use the 741 that you have if you want to use dual supplies.
 
The actual voltage when sensor is static is 0.2 volts with sensor supply voltage is 3.3.

full deflection senor gives out -0.8 volts to + 1 volt

I need to convert this to 0 volts to 5 volts with 2.5 when static.
Any suggestions on values?
 
paul200 said:
The actual voltage when sensor is static is 0.2 volts with sensor supply voltage is 3.3.

full deflection senor gives out -0.8 volts to + 1 volt

I need to convert this to 0 volts to 5 volts with 2.5 when static.
Any suggestions on values?
Are you sure it's level? Its output is a function of levelosity (to coin a word).
 
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