Formula for calculating capacitor charging and discharging time and charging current

Set the initial voltage of the capacitor value is V0 ;V1 for eventually rechargeable capacitance or voltage value;V t as moment capacitor of the voltage value., n = " V0" + (V1 - V0) * (1 - exp (-t/RC)] or, RC * t = Ln (V1 - V0)/(V1 - Vt)], for example, the voltage E battery goes through R initial value of zero capacitance C charge V0 = 0, V1 = E, so charge voltage of capacitor at T time is

Set, where V0 is the initial voltage on the capacitor value;

V1 for capacitance eventually rechargeable to or on the voltage value;

N t moment capacitor on the voltage value.

Then,

Vt="V0"+(V1-V0)*[1-exp(-t/RC)]

Or,

t=RC*Ln[(V1-V0)/(V1-Vt)]

For example, the voltage of battery by R E capacitance C charging to the initial value of 0

Where V0 = 0, V1 = E, the charge to the capacitor on the voltage of t time:

Vt="E"*[1-exp(-t/RC)]

Such as, the initial discharge voltage of capacitance C by R E

Where V0 = E, V1 = 0, so on the capacitor on the voltage of t time:

Vt="E"*exp(-t/RC)

And, as the initial value for a third VCC capacitance C by R charging, charging terminal value is zero

Vcc, ask charge to 2/3 Vcc need how much time?

Where V0 = Vcc / 3, V1 = Vcc, n = 2 * Vcc / 3, so

t="RC"*Ln[(1-1/3)/(1-2/3)]=RC*Ln2

=0.693RC

Note: the above exp () said to the exponential function of e at the bottom;Ln () is at the bottom of logarithmic function e

The page contains the contents of the machine translation.