I want to be able to convert a voltage from Arduino, from 0 to 2.5v to a voltage that is -5v to 5v. Scalable though. So Arduino output of 0v to 2.5v and then convert that to -5v to +5v.
I realise that I will have to use some amount of Operational Amplifiers.
From my knowledge of Op-Amps, I understand that I could use 3, and initially multiply the voltage by 2, giving 0 to 5 v, then use a Sum op-amp circuit and -2.5v which will leave -2.5v to +2.5v and then I could multiply that by 2, which would give -5v and +5v.
You only need a single op amp. Make an inverting amplifier with a gain of 2 and connect the + input to + 2.5 V using a potential divider of two equal resistors off the 5V supply.
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It seems like a very smart way to deal with what is required, and wondering if there is still anyone around these forums with the electronics know-how required to tell me if what I want to do is possible with one Op-Amp and a potential divider?
More information needed. What Arduino are you using. How are you getting the 0 to 2.5V. then scaling it to +-5 V. Why not simply use a DAC (Digital to Analog Converter), it will do the work for you.
First consideration is to know the "analog" output of an Arduino (one that does not have a DAC built in) is really a PWM signal whose average is the requested analog voltage. So first you will need to filter the PWM, this will slow down its response time.
Then you will need a -5V supply. Greater than -5v if being close to -5 is not good enough (in this context -6 is greater than -5.
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