ADS4222EVM: Differential inputs for ADS4222EVM

Danilo A.

Part Number: ADS4222EVM

Hi Team,

We would like to ask your help regarding the customer's inquiry below.

I would like to convert the single-ended ports of ADS4222EVM to the differential ones. I attached the modified schematic. Could you please confirm it? Also, please specify what resistor size is needed to short T1/T2. (Based on the schematic, I assume that the same changes are needed for CH-B to convert it to differential pair).

Regards,

Danilo

over 3 years ago

0 Amy over 3 years ago

TI__Genius 15321 points

Hi Danilo,

To convert the single-ended ports to differential, install a connector at J7 and remove the resistor at R67. It is best to install a 0.1uF capacitor at R66 to balance the signal with the input at J6. There is no need to short or modify the two transformers, as they will not have an impact on the differential input.

0 Danilo A. over 3 years ago in reply to Amy

TI__Mastermind 27250 points

Hi Amy,

Thank you for your response. Here is a follow up question from our customer,

Can I also use resistors at C11 and R66 to balance the circuit? (I am asking this because currently I don't have capacitor (402 size) to be added at R66).

Regards,

Danilo

0 Amy over 3 years ago in reply to Danilo A.

TI__Genius 15321 points

Hi Danilo,

Using resistors at C11 and R66 should be ok too. The main consideration is to ensure that C11 and R66 have the same resistor values so that the differential input signal is balanced.

0 Danilo A. over 3 years ago in reply to Amy

TI__Mastermind 27250 points

Hi Amy,

Thank you very much for your help.

Regards,

Danilo

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ADS4222EVM: Differential inputs for ADS4222EVM