Shifting 0-5V signal to -2.5-2.5V

  • Thread starter Thread starter bassplayer142
  • Start date Start date
  • Tags Tags
    Signal
AI Thread Summary
To shift a 0-5V signal to a -2.5 to 2.5V range, a unipolar to bipolar converter circuit is recommended, typically using an op-amp voltage difference amplifier. A bipolar power supply of at least +5V and -5V is necessary for this setup. For audio signals, a large capacitor in the signal line may suffice, or a resistor divider to a negative supply could be an alternative. The application involves a laser scanner system, where an adjustable supply is crucial for testing. Overall, the discussion highlights various methods to achieve the desired voltage shift effectively.
bassplayer142
Messages
431
Reaction score
0
Shifting 0--5V signal to -2.5--2.5V

I have a DAC coming from my micro with a signal that will vary anywhere from 0-5Volts. What are my options of shifting that down so I can get a -2.5 -- 2.5V swing? Thanks!
 
Engineering news on Phys.org


In a op-amp voltage difference amplifier, you could subtract 2.5V from the input:

diffa2.gif
 

Attachments

  • diffa2.gif
    diffa2.gif
    2.7 KB · Views: 1,884


For this setup I will need to supply a positive voltage on pin 7 and a negative one on pin 4 right? thanks
 


bassplayer142 said:
For this setup I will need to supply a positive voltage on pin 7 and a negative one on pin 4 right? thanks

Yes, about +5 / -5 volts DC at a minimum.

There may be a much simpler solution but without a more detailed description of the nature of the signal then you mightn't get it.
 
Last edited:


Yes, you need a bipolar power supply. Your circuit is a unipolar to bipolar converter. If interested, I have an article about this type of circuit here:

Design a Unipolar to Bipolar Converter for a Unipolar Voltage Output DAC
http://masteringelectronicsdesign.com/design-a-unipolar-to-bipolar-converter-for-a-unipolar-voltage-output-dac/"
 
Last edited by a moderator:


From your name, bassplayer, I'm thinking that you have an audio signal?

If it is over 10Hz or so, presuming that the destination is biased around 0v, you might be able to just put a big capacitor in the signal line. You might also get away with using a resistor divider to a negative supply voltage without bothering with an Op-Amp.

What's your actual application?
 


Actually I'm working on a laser scanner system for light show with some mirror galvanometers. I don't have a datasheet on them or any type of function generator so having an easily adjustable supply will be great for finding the limits of operation. Thanks for all the posts, its been a great help!
 


Then they are pretty much just speaker voice coils, and a inline capacitor will do the trick. However you probably need more power than the PC output can push. Perhaps more than the PC headphone output too, but you could try that or a small powered speaker system for a start.
 

Similar threads

Replies
18
Views
2K
Replies
5
Views
8K
Replies
7
Views
232
Replies
12
Views
3K
Replies
27
Views
3K
Replies
4
Views
3K
Replies
1
Views
2K
Back
Top