TMS320F28P550SJ: Possible Cross-talk when using AIO as Digital Inputs?

Marinus Holzner

Intellectual 1940 points

Part Number: TMS320F28P550SJ

Hi ASM-Team,

I want to use the AIO Pins as digital Inputs, but I saw that there is a comment regarding cross-talk on the datasheet:

2026-01-16 17_17_49-TMS320F28P55x Real-Time Microcontrollers datasheet (Rev. C) - tms320f28p550sj.pd.png

Do we have more precise documentation when this might be an issue and how this can be avoided?

The goal is to use all the AIO Pins as digital pins only.

Thank you,

Marinus

3 months ago

0 Marinus Holzner 3 months ago

TI__Intellectual 1940 points

Hi,

do you have any updates on this thread?

Thank you,

Marinus

0 Marinus Holzner 2 months ago in reply to Marinus Holzner

TI__Intellectual 1940 points

Hi again,

one more ping. Do you have any updates yet?

Thanks,

Marinus

+1 Masoud Farhadi 2 months ago in reply to Marinus Holzner

TI__Expert 7260 points

Hi Marinus,

That datasheet note is specifically warning about substrate/package coupling: if you bring fast-edge (high dv/dt) digital signals onto AIO/ADC pins, those edges can capacitively couple into nearby analog channels and show up as noise / error when those adjacent channels are being used as analog inputs.

If your plan is to use all AIO pins as digital inputs only and you are not using adjacent ADC channels for analog measurements, then this warning is generally not a concern, because there isn’t a sensitive analog measurement to corrupt.

Best Regards,

Masoud

C2000™︎ microcontrollers

C2000 microcontrollers forum

TMS320F28P550SJ: Possible Cross-talk when using AIO as Digital Inputs?