ADS131A04EVM: SE application

Ben Kuo

Expert 6695 points

Part Number: ADS131A04EVM
Other Parts Discussed in Thread: ADS131A02

Dear team,

Customer would like to design single-end input to ADS131A02.

And I found an E2E post which we can disable VNCPEN by software for SE application.

Did you have schematic example for SE application? Could you share it with customer?

Regards,

Ben

over 3 years ago

0 Ryan Andrews over 3 years ago

TI__Guru 57296 points

Hello Ben,

Thank you for your post.

The negative charge pump allows for the input signal to swing below GND while only using a unipolar analog supply. Without the negative charge pump, the customer would need to use bipolar analog supplies instead, such as +/- 2.5 V. Bipolar supplies allow the input voltage to swing above and below GND.

Regards,

0 Ben Kuo over 3 years ago in reply to Ryan Andrews

TI__Expert 6695 points

Hi Ryan,

I would like to double confirm with you.

According to EVM and datasheet, Are below items correct?

1. AINxP connect to SE analog input. AINxN can let it floating.

2. If analog input signal is always above GND, can we disable negative charge pump/ connect AVDD to 5V and AVSS to GND?

Regards,

0 Ryan Andrews over 3 years ago in reply to Ben Kuo

TI__Guru 57296 points

Hi Ben,

AINxN cannot be left floating. For a single-ended input, tie AINxN to GND.
Yes, if the single-ended input signal is always positive, the negative charge pump can be disabled and the analog supplies can be set to AVDD = 5 V and AVSS = GND.

Regards,

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ADS131A04EVM: SE application