ADC diagnostic - analog multiplexer and ADC core.

ICH · ‎Nov 12, 2021

Hello,

MCU: CYT2B7

according to the Traveo II TRM (revision H)paragraph:

31.4.1 Preconditioning - this is a safe diagnostic feature, which verify the state of the "external" wiring short to GND,VCC and open load.

31.4.3 SARMUX diagnostics - this feature allow verification the connection from SARMUX input pin (I understand this like input physical pin ) to the sampling capacitor.

According to the AN219755 paragraph 8 Diagnosis function, which explain ADC diagnostic "Overlap diagnostics mode'' is not enabled.

The question:

I would like to do self diagnostic of the ADC, which include the input multiplexer and ADC core.

Is the algorithm explained in the app note AN219755 is suitable for this purpose or other algorithm including SARMUX diagnostics, should be used?

Best regards,

ICH

Ashish · ‎Nov 21, 2021

Hi,

Sorry for delay. For the original question-for the testing based on preconditioning, it is assumed that the core is functional, and VrefH , VrefL are correct (there is no option to change the reference voltage VREFH and VREFL internally to some other pin for testing purpose, so testing it itself won't be possible). Other things can be tested as described earlier.

For your MCAL queries, we suggest to contact local sales representative (as we can't discuss on community). But in general, as I already suggested VrefL/H can't be tested using ADC as the pin is fixed [refer datasheet for the pin]. Although you can provide VrefL/H to ADC channel input, and ideally VRefH should correspond to max digital output typically 0xFFFu and VrefL should correspond to min digital output typically 0x000u [refer the calibration procedure in the Appnote you mentioned, and also register PASSx_SARy_CHz_SAMPLE_CTL [5:0] PIN_ADDR] .

Best Reagrds,

Ashish

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ADC diagnostic - analog multiplexer and ADC core.

ADC diagnostic - analog multiplexer and ADC core.

Re: ADC diagnostic - analog multiplexer and ADC core.