I am tring to work with an ADC and i have one problem, the adc cannot see the negative alternance of the signal from the head, how can i shift the signal so all the wave from the head to be on the positive edge?

 

Originally posted by cosmin800@Aug 29 2005, 10:10 AM
I am tring to work with an ADC and i have one problem, the adc cannot see the negative alternance of the signal from the head, how can i shift the signal so all the wave from the head to be on the positive edge?

[post=10000]Quoted post[/post]​

Hi cosmin800,

I think what you are going to need is a differential amplifier that is powered from your positive supply. That way your read-head will be connected up as a floating signal source.

Can you post your present read-head interface circuit here?

hgmjr

 

Originally posted by cosmin800@Aug 29 2005, 06:10 PM
I am tring to work with an ADC and i have one problem, the adc cannot see the negative alternance of the signal from the head, how can i shift the signal so all the wave from the head to be on the positive edge?

[post=10000]Quoted post[/post]​

You could be lucky if the ADC in question can take a negative -ref input, but the best is for you to post the schematic here.

TOK

 

You should search for an ADC reference book or application guide on-line from a chip vendor, such as these:

http://www.maxim-ic.com/appnotes.cfm/appnote_number/1108
http://www.analogzone.com/acqt1101.pdf