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TMDSCNCD28P65X: ADC with DAC communication error

Part Number: TMDSCNCD28P65X


Tool/software:

Hi Everyone, I hope everyone is doing well. I am new to the Electrical Domain how the ADC and DAC works technically on differential mode for the Texas board. My goal is to handle the ADC Interrupt trigger SOC with PWM state. I have used ADC to DAC configuration for texas board to trace the input voltage in between the 3300mv. Goal is to handle identify the input voltage change state based on the resolution and the ADC_REF_VOLTAGE. Following the formula  inputVoltage_mV = (adcValue * ADC_REF_VOLTAGE) / ADC_RESOLUTION;. I am able to see the change in the ADC and DAC value state but still unable to get any updated value for the inputVoltage_mV for the following logic. Can anyone give me advise how to achieve the following 

A. If the input voltage is between 0 and 1V, the Duty cycle of ePWM3A should be 30%.
B. If the input voltage is between 1 and 2V, the Duty cycle of ePWM3A should be 50%.
C. If the input voltage is between 2 and 3V, the Duty cycle of ePWM3A should be 70%.

I am not using any external device here. I am using same texas board 

where A0 pin I am using as VDACC_OUT connected with the ADC_B B0 pin as positive voltage state

B1(-) connected with the gnd here 

EPWM is GPIO Pin connected with the logical analyzer for the EPWM3A and EPWM3B.

Can anyone please help in this. Thank you

  • Hi Ahmad,

    I wanted to make one thing clear here:

    A0A1 are differential...where A0 is positive A1 is negative channel.

    B0 B1 are differential. Where B0 is positive B1 is negative channel.

    Following the formula  inputVoltage_mV = (adcValue * ADC_REF_VOLTAGE) / ADC_RESOLUTION;.

    Can you please elaborate on this formula?

    Thanks,

    Susmitha