Hi,
But the same slope evaluated using micro controller would generate the requisite slope at RC time and not 5RC. Would that be wrong?
I guess the digital processing works well, but your assumption is wrong.
(since we don´t see: your analog circuit, code, your expectation, your digital results)
In the analog world you have
* volts
* and time
in the digital world
* volts are converted to binary code (LSBs) by the ADC. --> you need to know the conversion factor for LSB/Volt.
* time is given by the ADC sampling frequency. --> You need to know the sampling frequency. It needs to be meaningful, fixed and stable. (you may also work with sampling period time, which is 1/fs)
For high dV/dt you may simply use dV/dt = val(t) - val(t-1)
For low values you should consider to use dV/dt = (val(t) - val(t-n)) / n.
Where n should be 10 or higher. Maybe even 1000. But mind you need to use a ring buffer to store all the values.
This gives you less noisy and more smooth output.
Klaus