Power Supply


The power supply provides a quick and convenient means of supplying voltage to a circuit.

Much like an actual bench power supply, the power supply instrument provides a selectable output voltage(s). Both regulated and unregulated power supply types are available and the actual current delivered to the circuit is displayed. Unlike an actual bench regulated power supply, the power supply instrument allows a degraded mode, wherein it functions like an unregulated power supply with ripple on its output, much like an actual raw DC power supply.

The output voltage is set in voltage-selection edit box. If voltage-regulated performance is desired, then select the Regulated button for type. On the other hand, if you wish to simulate a cheap power supply, such as a wallwart, then select Unregulated for type and set the regulation to 25%, the noise to 500mV and the current to the idle current of your circuit. The regulation percentage refers to the over voltage an unregulated power supply develops when unloaded. Thus, a 10-volt/1-amp power supply with 10% regulation will putout 11 volts when it isn’t delivering any current and 10 volts when delivering its rated output current of 1A. 0% regulation means the power supply is indifferent to output current variations, as it produces a constant output voltage. The power supply noise’s frequency equals twice the wall voltage’s frequency, for example, 120 Hz, when the wall voltage is at 60 Hz. The noise’s waveform is selectable. Actual capacitor smoothed power supplies produce a triangular noise waveform; choke input power supplies, something closer to a sine wave waveform; and some switching power supplies, a square wave waveform.