ADCM362

we are working with aducm362. Our need is to do an oversampling by operating o sinc2 filter along with sinc4 filter. We have configured all the registers according the hardware reference manual and datasheet, but we are not getting the ready interrupt.What is the method to set the step detection threshold? How we can make it working ? is there any example codes available which will  do over sampling ?

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    •  Analog Employees 
    on Oct 16, 2018 10:32 AM over 2 years ago

    Hi,

    Sorry, no example code for this case.

    The register for setting the step detection threshold is STEPTH register, there are total 1024 steps. To enable the step detection, please note the below information.

    1. Configure DETCON register.  Be sure to enable the SINC2 (bit[7]), select the used ADC (bit[6]), and correct RATE (bit[1:0]). An example of function is shown below.

    AdcDetCon(pADI_ADCSTEP,DETCON_SINC2_EN,DETCON_ADCSEL,DETCON_RATE_2ms);

    2. Configure the STEPTH register to make sure the threshold.

    3. Interrupt is recommended to use. The interrupt for step detection is sinc2 interrupt not ADC interrupt. The function of interrupt is shown below.

    SINC2_Int_Handler()

    4. Be sure to enable ADC conversion.

    Regards

    Barry

  •   When we use sinc3 filter of ADC1, The Sigma Delta modulator has frequency of 125KHz, the OSR is found out by OSR= Fs/Fn, where Fn = 2* Nyquist rate.i.e, 125KHz/Fn is our OSR. since the frequency of input signal will be always a constant value so the Fn also will be a constant value, then how can we vary OSR ? we can control the SF and AF, but with this we can alter only the  decimation factor. How we can achieve a control over  OSR ? Also the final data we get through ADC1DAT register and the conversion equation given is (Vref/2^28) * ADC1DAt and also it is given that we will get an output of 1.2V. in thgis register our data will be of 21 bits, if we substitute the maximum value of 21 bit it will gives an output of 19mv only. Please give a solution for how we can use the over sampling functionality of sinc3 filter and how we can take the correct data out? 

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  •   When we use sinc3 filter of ADC1, The Sigma Delta modulator has frequency of 125KHz, the OSR is found out by OSR= Fs/Fn, where Fn = 2* Nyquist rate.i.e, 125KHz/Fn is our OSR. since the frequency of input signal will be always a constant value so the Fn also will be a constant value, then how can we vary OSR ? we can control the SF and AF, but with this we can alter only the  decimation factor. How we can achieve a control over  OSR ? Also the final data we get through ADC1DAT register and the conversion equation given is (Vref/2^28) * ADC1DAt and also it is given that we will get an output of 1.2V. in thgis register our data will be of 21 bits, if we substitute the maximum value of 21 bit it will gives an output of 19mv only. Please give a solution for how we can use the over sampling functionality of sinc3 filter and how we can take the correct data out? 

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