ADS1263: Calibration Probleam

tushar gajjar

Prodigy 60 points

Part Number: ADS1263

Tool/software:

Hi team

I am using ADS1263 on our custom board.

My goal is to measure current using shunt (20 mill ohm resistor).

but when i perform Self offset calibration i getting random value of calibration.

like 0xFD then i power off the board and again powered and perform self offset calibration this time i got 0xC8.

again repeat power cycle of our board i am different value like 0x80 .

Thanks ,

Tushar Gajar

6 months ago

0 Bryan Lizon86 6 months ago

TI__Guru 52626 points

Hi tushar gajjar,

Is this related your post here about the ADS1263EVM? I never received a response to that post, did you get the calibration to work on the EVM and now cannot get it to work on your custom board?

https://e2e.ti.com/support/data-converters-group/data-converters/f/data-converters-forum/1490677/ads1263evm-pdk-calibration-probleam?tisearch=e2e-sitesearch&keymatch=%252520user%25253A628499#

The offset calibration requires a valid voltage reference to operate, so ensure that you have a reference voltage applied (if you are using an external reference) and that the correct reference voltage source is selected in the ADC register map

Can you also report your offset values as 24-bit values? It's hard to know what is meant by 0xC8 - is that 0x0000C8? Keep in mind that the offset should be a very small number, and can be negative. You should also try converting the codes to voltage to see if the result makes sense

-Bryan

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ADS1263: Calibration Probleam