ADuCM355 Cyclic Voltammetry Example Current Conversion Formula


I am testing the Cyclic Voltammetry example from the SDK on a devkit with no software modifications using a 1k ohm star resistor load. I am having trouble converting the RAW current ADC values output on the UART to actual current. In reference to page 59 of the hardware users manual, it mentions the addition of ADC_VBIAS_CAP in the formula when PGA is 1. It looks like the ADC is actually configured as so:

Positive input: HPTIA Output

Negative inpute: HPTIA Inverting Input

With the above in mind, can you answer the following questions?

1. What the the correct ADC count to voltage conversion formula for this configuration?

2. To calculate current, I assume the formula is:

I = (-V_ADC / R_TIA)



Corrected formula
[edited by: droberson at 2:26 AM (GMT -4) on 3 Sep 2020]

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