TMS320F28P550SJ: ADC Result

Seamus Pu

Part Number: TMS320F28P550SJ

Tool/software:

Hi Expert,

I used P55 controlCARD and adc_ex1_soc_epwm to evaluate the ADC module. I found that if I sample the floating channel, the ADC value will changed around 200. Is this normal? How can I explain it?

Best Regards,

Seamus

over 1 year ago

0 Ibukun Olumuyiwa over 1 year ago

TI__Genius 11071 points

Hello Seamus,

The converted value of a floating channel is not predictable.

Best regards,
Ibukun

0 Seamus Pu over 1 year ago in reply to Ibukun Olumuyiwa

TI__Intellectual 830 points

Hi Ibukun,

Does the module need to be corrected in some way? Because this offset is really quite large.

Best Regards,

Seamus

0 Ibukun Olumuyiwa over 1 year ago in reply to Seamus Pu

TI__Genius 11071 points

Hello Seamus,

I don't know how you correct a floating pin. By definition it can be any voltage within the operating range. If you want the converted value to be predictable, then add a pull-up or pull-down resistor to the pin.

Best regards,
Ibukun

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TMS320F28P550SJ: ADC Result