ADS1292RIRSMT schematic review

Victor Chen_HK

Expert 5130 points

Other Parts Discussed in Thread: ADS1292R, ADS1292

Hi Team,

Could you please help to review the attached schematic of ADS1292R?

My customer wants to use the circuit to measure electromyographic signal.

ADS1292RIRSMT.pdf

Thanks and best regards,

Victor

over 9 years ago

0 Tom Hendrick over 9 years ago

TI__Guru**** 181021 points

Hi Victor!

Your ADS1292 schematic is very close to what we show in the users guide for the EVM, so I do not have any major concerns. Please feel free to send me the layout before you have boards made and we'll look over that as well.

0 Joseph Wu over 9 years ago

TI__Guru* 98015 points

Victor,

I would generally avoid using any inductances in the supply. With most ADCs we will have currents spikes associated with any digital clocking or capacitive sampling. These currents spikes will often cause large voltage spikes with the supply inductance. Also note that with L1 and the supply bypass capacitors, you will most certainly have some sort of ringing.

If they want to leave L1 in the schematic, they can, but they may need to replace it with a simple short later on.

Joseph Wu

0 Victor Chen_HK over 9 years ago in reply to Joseph Wu

TI__Expert 5130 points

Tom, Joseph,

Thanks a lot for your reply and suggestion.
Is there any problem to connect ERL and ELL together? I noticed that the EVM has a different connection.

Another question is that why you need to measure both DC and AC differential signal of ELA and ELR?

Thanks and best regards,

Victor

0 Tom Hendrick over 9 years ago in reply to Victor Chen_HK

TI__Guru**** 181021 points

Hi Victor,

I don't see where ERL and ELL are connected together. ERL comes from R4 and originates at RLDOUT. ELL goes through R13 and into IN2P. The AC coupled channel allows for respiration measurement.

0 Victor Chen_HK over 9 years ago in reply to Tom Hendrick

TI__Expert 5130 points

Hi Tom,

Thanks for the feedback.
Would you please help to check the layout and share your comments as well?
Many thanks.

Best regards,
Victor

0 Tom Hendrick over 9 years ago in reply to Victor Chen_HK

TI__Guru**** 181021 points

Hi Victor,

Yes, please send the layout detail directly to me via e-mail.

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ADS1292RIRSMT schematic review