#### hkBattousai

##### Member

***broken link removed***

I want to measure power and show it on an LCD display using a microcontroller. The MCU has a A/D convertor with 10-bit resolution. In the picture above, I have calculated and illustrated the PDFs (probability density function) of probability of error (I assumed that the error would have a uniform probability).

Now, I know the PDFs of error functions of both i (the current) and v (the voltage). So, how can I calculate the PDF of error function of power (p = v . i)? Will this function have a uniform PDF too? I know that PDF of sum of two probability functions is the convolution of their respective PDFs, but what about the case of multiplication?

My main purpose is to determine the resolution of my circuit output, in other words, the number of meaningful digits after comma on the LCD screen. But I also wonder the mathematical background of this calculation.