RC Charging Circuit
When a voltage source is applied to an RC circuit, the capacitor, C charges up through the resistance, R
The charging of a capacitor is not instant as capacitors have i-v characteristics which depend on time and if a circuit contains both a resistor (R) and a capacitor (C) it will form an RC charging circuit with characteristics that change exponentially over time.
All Electrical or Electronic circuits or systems suffer from some form of “time-delay” between its input and output terminals when either a signal or voltage, continuous, ( DC ) or alternating ( AC ), is applied to it.
This delay is generally known as the circuits time delay or Time Constant which represents the time response of the circuit when an input step voltage or signal is applied. The resultant time constant of any electronic circuit or system will mainly depend upon the reactive components either capacitive or inductive connected to it. Time constant has units of, Tau – τ
When an increasing DC voltage is applied to a discharged Capacitor, the capacitor draws what is called a “charging current” and “charges up”. When this voltage is reduced, the capacitor begins to discharge in the opposite direction. Because capacitors can store electrical energy they act in many ways like small batteries, storing or releasing the energy on their plates as required.