Where: "-" is a negative number; resistor R and capacitor C are in series, R units of ohms, C in units of F; E for the series resistance and capacitance between the voltage, V for the capacitor voltage to be achieved between. ln is the natural logarithm, in the EXCEL system has a function to calculate very convenient.
After comparing the actual calculation is consistent.
For example: R (150K) and C (1000UF) between the voltage of 12V, when the capacitor C bipolar voltage of 3 volts when the time:
RC charging circuit according to the formula: Vc = E (1-e-(t / R * C)) the projection
R = 2.2KC = 100PF. Supply voltage of 20V. I want to know both ends of capacitor voltage from 0V to 13V up the time spent T how calculated? This more practical, initial state and final state have the