RC Circuit Transient Calculator
Analyze capacitor voltage/current over time for RC charge and discharge.
RC Circuit Transient Calculator models capacitor voltage during charging or discharging through a resistor. An RC circuit contains resistance R and capacitance C, and its characteristic time constant is tau = R*C. After one time constant, a charging capacitor has moved about 63% of the way toward the supply voltage; after about five time constants, it is effectively settled for many practical purposes. During discharge, the voltage falls exponentially rather than linearly, so equal time intervals produce proportional rather than equal voltage drops. This tool is useful for timing circuits, filters, sensor smoothing, and electronics coursework. Real circuits may deviate because of leakage, tolerance, source resistance, load impedance, and nonideal capacitor behavior.