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Re: Cap voltage - time



Original poster: "Antonio Carlos M. de Queiroz by way of Terry Fritz <twftesla-at-uswest-dot-net>" <acmq-at-compuland-dot-com.br>

Tesla list wrote:
> 
> Original poster: "Jim Lux by way of Terry Fritz <twftesla-at-uswest-dot-net>"
<jimlux-at-earthlink-dot-net>
> 
> When charged from a constant current source, V = I * T/C
> When charged from a constant voltage source through a resistor
> V = Vcharge * (1-exp(-T/(R*C))
> where exp(x) is e^x, where e = 2.71828459045....
> Units: Ohms, Volts, Farads(!), Seconds

For general calculations, the first formula is very useful. It is
the simplest case of the general case for linear capacitors:

V(t0+T)=V(t0)+1/C*Integral from t0 to t0+T of I(t)

If you know the average value of the current I in the time interval T: 

Variation in V = (T/C)*Average of I.

(e=2.7182818284...) 

Antonio Carlos M. de Queiroz