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Differential pulse voltammetry on ADuCM355

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Hello,

I'm developing a DVP code based on https://ez.analog.com/dsp/f/q-a/550406/differential-pulse-voltammetry-on-ad5941 and I'm having two questions:

1. I can adjust the frequency on M355_SqrWaveVoltammetry example without problems and I can check it on oscilloscope, but using the previous DVP code when I put 25 HZ (  pRampCfg->Frequency = 25;  /* Frequency of square wave in Hz */) I'm obtaining a period of 120ms (checked on oscilloscope). does anyone know why?

2. I'm using a Palmsens (EmStat Pico Development Kit ) kit to compare my results, and on my solution I'm getting apparently the right curve but the output of current value is different when compared with Palmsens, please look bellow:

On the first peak, the value is 223 uA (ADuCM355 )  and on the second is 9.12uA ( PalmSense)

My configuration on ADuCM355:

    /* Step 2:Configure square wave signal parameters */
  pRampCfg->RampStartVolt = -500;           /* -0.5V */
  pRampCfg->RampPeakVolt = +500;            /* +0.5V */
  pRampCfg->VzeroStart = 1000.0f;               /* 1.3V */
  pRampCfg->VzeroPeak = 1000.0f;                /* 1.3V */
  pRampCfg->Frequency = 40;                /* Frequency of square wave in Hz */
  pRampCfg->SqrWvAmplitude = 200;                /* Amplitude of square wave in mV */
  pRampCfg->SqrWvRampIncrement = 10;             /* Increment in mV*/
  pRampCfg->SampleDelay = 5.0f;                /* 10ms. Time delay between DAC update and ADC sample. Unit is ms. */
  pRampCfg->LPTIARtiaSel = LPTIARTIA_8K;      /* Maximum current decides RTIA value */

My configuration on Palmses is:

does anyone know what can be happening?

thanks in advance,