Hello electronics experts,
I do not yet have enough reputation to post more then two images. For the images please see: https://i.stack.imgur.com/imDns.jpg
I have a single ended signal that i want to convert to be differential so that I can use the full scale of the differential ADC (ADS1278).
The single ended signal that i want to use is 0V - 2.5V. The ADC input range goes from +Vref to -Vref, i have the Vrefp tied to 2.5V and the Vrefn tied to ground. To convert the signal a THS4521 differential amplifier is used.
Now from what I know, when the single ended signal looks like image 1 the differential signal should look like image 2.
But when I use the single ended to differential schematic from the amplifiers datasheet image 3 (Vocm is set to 1.25V), The output of the amplifier gives me the signal of image 4.
I can see that the pk-pk voltage of this resulting differential signal is the same as the single ended signal (2.5V). But is is different from what I thought that was going to happen (image 2). Can anyone explain to me why this happens or what I am not understanding about differential signals?
Thank you, Sisco