TMS320F28335 ADC question

a0321875

Prodigy 550 points

Customer has the below question.

Thanks, Rob

TMS320x2833x Analog-to-Digital Converter

(ADC) Module

Reference Guide

Literature Number: SPRU812A

September 2007–Revised October 2007

The app note for the ADC says:

The ADCOFFTRIM register is pre-loaded by the ADC_cal routine in the boot ROM.

Please explain how the boot ROM determines the value to put in the ADCOFFTRIM register. Is it variable or a fixed value programmed by the factory?

over 15 years ago

0 Lori Heustess over 15 years ago

TI__Guru* 93340 points

a0321875 said:

The app note for the ADC says:

The ADCOFFTRIM register is pre-loaded by the ADC_cal routine in the boot ROM.

Please explain how the boot ROM determines the value to put in the ADCOFFTRIM register. Is it variable or a fixed value programmed by the factory?

Rob,

The value is determined by TI during test and is specific for a particular device. The value is such to put the ADC within specifications foun din the data manual.

More info on this wiki page: http://processors.wiki.ti.com/index.php/Analog_to_Digital_Converter_Type_2_FAQ_for_C2000

Regards,

-Lori

0 tamir friedrich over 14 years ago

Prodigy 40 points

Hello, I have a ADC related question as well, regarding calibration:
Following a simple re-layout of the board, we are getting x10 noisier read-out from the ADC's channels, for a reference HW based 0 volt input. We found out it is possibly related to the power-up sequence of the voltage feeds, yet we are not sure about it.
Anyone experienced such a behaviour or can give me some directions to look for?

Your helpis much appreciated, Tamir, ACS tamirf@acsmotioncontrol.com

0 tlee over 14 years ago in reply to tamir friedrich

TI__Guru 62975 points

Tamir,

If you do not receive any feedback about your issue, please start a new thread for your question. Older topics that have been answered are generally not monitored.

-Tommy

C2000™︎ microcontrollers

C2000 microcontrollers forum

TMS320F28335 ADC question