ADS1299: Multiple ADS1299 Biasing Config

Meerkat21

Part Number: ADS1299

Hello,

I am a undergraduate student working on a senior project that seeks to develop a 24 channel EEG acquisition system that utilizes 3 ADS1299.

Currently, I am uncertain if my design for the biasing electrode and referencing electrode are correct. We will be using SPI communication with daisy chain configuration. Additionally, we are wanting to have BIAS_IN be driven by either the BIAS_ELECT or a onboard mid-supply as shown within the EEG Front-End Performance Demonstration Kit (slau443) page 50.

Can anyone verify whether my circuitry is correct?

Thank you for your time.

over 4 years ago

0 Praveen Aroul over 4 years ago

TI__Mastermind 49906 points

Hello Meerkat,

The configuration looks fine.

I am assuming you will power down the bias amp of dev #2 and dev #3.

0 Meerkat21 over 4 years ago in reply to Praveen Aroul

Prodigy 20 points

Thank you for responding.

Yes, we will be powering the bias amps down on dev#2 and dev#3. Just to clarify though, if we didn't power down the bias amps on dev#2 and dev#3 would that cause any degradation of the signal? We are assuming it would just be consuming unnecessary power if left powered on.

0 Praveen Aroul over 4 years ago in reply to Meerkat21

TI__Mastermind 49906 points

Since the BIAS_OUT for the other devices (#2 and #3) are not connected together, turning on the bias amps on dev #2 and #3 would just be consuming unnecessary power.

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ADS1299: Multiple ADS1299 Biasing Config