duction Charging Mode RC circuit is a circuit composed of resistors and capacitors. If the switch in the figure 1 is closed, then the current will flow in the circuit and it start charging the capacitor. The voltage of the capacitor will change as a function of time: V_C=V_0 (1-e^(-t/)) The charge of the capacitor will change as a function of time: Q_C=CV_C=CV_0 (1-e^(-t/))=Q_0 (1-e^(-t/)) Where is the battery voltage, C the capacitance of the capacitor, Q_0 is the maximum charge, and is called the time constant and it is the time needed to charge the capacitor to 63% of the total charge. =RC Where R is the resistance of the resistor