ADS1298 unipolar supply questions

Gergo Santha

Other Parts Discussed in Thread: ADS1298

Hi,

my design of ADS1298 would use the unipolar supply according to the datasheet. I'm not any good in analog design so excuse me for the dumb questions but I would like to know more about the input signal level shifting. Is it an internal feature (eg the chip would do it for me) or I need to set its registers or I need to design a level shifter?

Any help is much appreciated.

over 14 years ago

0 Tom Hendrick over 14 years ago

TI__Guru**** 180941 points

Hi JustGreg,

The ADS1298 does not compensate for CM input range on its own, you would have to take care of that on yourself. Please refer to this post for details on the analog input requirements and the assocoated tradeoffs with sampling ECG signals with single ended or bi-polar power supplies:

http://e2e.ti.com/support/data_converters/precision_data_converters/f/73/t/72705.aspx

Josh Wojnas - one of the more prominent community members in this forum, has some open source code and layout detail for the ADS1298, I would suggest you take a look at his material as well. You might find it useful.

0 Gergo Santha over 14 years ago in reply to Tom Hendrick

Genius 3585 points

Thanks Tom.

0 josh wojnas over 14 years ago in reply to Tom Hendrick

Intellectual 805 points

Thanks for the referal also the open simplified design = less pinouts is a good way to get someone started a framework and that schematic in kicad that they can download make it easy for them to not reinvent the weel for specific designs.

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ADS1298 unipolar supply questions