TMS320F28335: ADC considerations

esmaeil ch

Part Number: TMS320F28335
Other Parts Discussed in Thread: TMDXIDDK379D

I have an application to drive an inductive motor, so i need to read and monitor it's current

i use lts25np module to measure the current and i read it by TMS320F28335's ADC

so what are ADC considerations that i should observe in this application?(should i use any filter or is there any EMI considerations?)

thank u

over 6 years ago

0 MatthewPate over 6 years ago

TI__Guru* 82800 points

I looked back to some of our motor control designs (http://dev.ti.com/tirex/explore/node?node=AJdHz0LdRqISE26F0bk69Q__0.jXikd__LATEST ) and see that when we use a LEM sensor we typically buffer it with something like TI http://www.ti.com/product/OPA2350 . I also see that we have biased the inverting input with the GND pin of the LEM, which is I assume limit the impact of any ground noise to the ADC reading.

In terms of the buffering the OPA provides, you may not require this if your system can afford a slower ADC sampling rate, as we provide a way to increase the sample and hold duration(AQCPS register) at the ADC. However, I think there is still value in being able to have the ground bias removed with the op-amp.

If you want to view the full schematics you will need to install our Motor Control SDK, and then look at the TMDXIDDK379D project. http://www.ti.com/tool/C2000WARE-MOTORCONTROL-SDK

Best,
Matthew

C2000™︎ microcontrollers

C2000 microcontrollers forum

TMS320F28335: ADC considerations