Resistor Capacitor circuit (RC circuit)
A resistor-capacitor (RC) circuit is a combination of a resistor and a capacitor connected in series or parallel to a voltage or current source. The resistor restricts the flow of current in the circuit, creating a voltage drop across it proportional to the current passing through. The capacitor, on the other hand, stores electrical energy in the form of an electric field when charged. When an RC circuit is connected to a voltage source, the capacitor charges up gradually through the resistor until it reaches its maximum charge (asymptotically). This charging process follows an exponential curve, characterized by a time constant, τ = R * C, where R is the resistance and C is the capacitance. This time constant defines how quickly the capacitor charges or discharges.
Types of RC circuit
RC circuit depending on the way the resistor and capacitor are connected can be classified in the following ways:
- Series RC circuit
- Parallel RC circuit
Series RC circuit forming a low pass filter
Step response
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Steady-state sinusoid response
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Frequency response
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Series RC circuit forming a high pass filter
Step response
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Steady-state sinusoid response
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Frequency response
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Parallel RC circuit
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Step response
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Steady-state sinusoid response
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Frequency response
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RC circuits have various applications in electronics, such as signal filtering, timing circuits, smoothing power supply voltages, and many other analog electronic systems. The behavior of an RC circuit depends significantly on the values of the resistor and capacitor and their arrangement within the circuit.