VCC (power supply)

A positive supply rail: pick a voltage, and everything wired to it sits there.

vcc has one pin and one job. It is not a battery with an internal resistance or a regulator that sags under load. It is an ideal source, which is what lets you build a 3.3 V circuit next to a 5 V one on the same canvas and have each side behave exactly as its own datasheet says.

Pins

Pin	What it does
VCC	Drives whatever net it is on to the chosen voltage.

Properties

voltage: the rail's voltage. 5 for a 5 V logic board, 3.3 for an ESP32-C3 or a Blue Pill, or anything else a circuit needs.

What the model gets right

The rail is a real source: anything you hang on it, from a single LED to a whole breadboard of 74HC chips, sees exactly the voltage you set, and the current it delivers is read back correctly on every part that probes its own current.

What it does not model

No internal resistance, no current limit, no sag. A real bench supply's rail dips a little under a heavy load; this one does not, because nothing here models a power budget. That is a deliberate simplification so a beginner's circuit is graded on its wiring, not on a supply that is secretly starving it.

It follows that nothing in Mokxi can ever brown out, and that is the single largest thing this simulator will not show you. A servo stalling, a WS2812 strip at full white, a relay coil and a motor on one regulator: all of them are real projects that fail on the bench for a reason nothing here can reproduce. There is no ripple, no noise, no turn-on ramp and no over-current shutdown either. The rail is at its voltage from the first instant and stays there.

Common mistakes

Two vcc parts at different voltages wired to the same net. The kernel resolves a net to the impedance-weighted mean of whatever drives it, so two ideal sources disagreeing gives an answer that is neither voltage, which is exactly the lesson a circuit with two supplies fighting each other is there to teach.

See it in action

Every circuit with no board in it needs one: Gate lab, NAND latch and 555 blinker are three you can open from /templates right now.