ADS1298 supply question

John Reyes

Other Parts Discussed in Thread: ADS1298

AVSS, AGND and DGND pins are connected to 0V, and AVDD, DVDD pins are connected to 3V. Would you have any problems obtaining ECG signals?

over 14 years ago

0 Tom Hendrick over 14 years ago

TI__Guru**** 180941 points

Hi John,

You can use the ADS1298 with a 0-3V analog supply, but you would need to be sure to bring the ECG inputs up to the common mode point of the ADC to have good results. Please take a look at this application note:

http://focus.ti.com/lit/an/sbaa160a/sbaa160a.pdf

That document describes the basics of the analog front end for ECG applications and goes over both a bipolar supply implementation as well as a single ended supply.

0 Ilia Davidov over 14 years ago in reply to Tom Hendrick

Intellectual 820 points

Hi John,

Please take a look at mentioned app.note and also to my topic http://e2e.ti.com/support/data_converters/precision_data_converters/f/73/p/61014/218756.aspx

As you see, due to bipolar natue of ECG signal, if you want to power your ADS1298 from single-polar supply (as AVSS is connected to AGND), you need to apply level shifting, otherwise your signal will be cutted-off (it's negative part).

Regards,

Ilia

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ADS1298 supply question