User manual

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Figure 3.3. Multisim RC Circuit
In this circuit, the FGEN output is a square wave with an amplitude of 5 V and a frequency of 100 Hz. At the output of
the FGEN, there is a 1 kΩ resistor in series with a 1 µF capacitor. This series RC circuit increases the time constant of the
circuit.
This means that the 10%-90% rise time of the square waveform, as measured across the capacitor, will be increased.
The time constant, τ=RC, of this circuit has a value of approximately 1 ms. You know that the 10%-90% rise time of a
square waveform can be characterized by the following equation: t
r
≈ 2.2τ.
This means that the 10%-90% rise time of the output should approximately be equal to 2.2 ms. In Figure 2.4, you have
taken an oscilloscope capture of the circuit simulation.