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I wish to create two circuits that reflect one power source output similar to the "VCC" symbol at https://www.physicsforums.com/attachments/image010-jpg.178004/. How can I do this in Circuit Lab where the closest symbol I can find is the two output "Voltage Source"? Thank you.

I have been told that Vcc was derived from "Constant Voltage at the Collector", which was the norm for early IC chips to be powered through a NPN's collector pin. Some OpAmp have a Vcc and a Vee pin, the Vcc being for the most positive voltage alimentation and Vee, the most negative voltage alimentation (traditionally, at an emitter pin of an NPN). That convention is not universal, though.

You should be able to reach your goal by using a DC voltage source set at the required voltage.

Thank you for the reply, vanderghast; I'm just confused what to do with the negative pole of the "Voltage Source" - can I just affix it to signal "GND (G)" and ignore it?

A Voltage Source can be a battery for constant voltage, or from an electrical wall outlet from the domestic distribution for an alternative voltage source.

In an isolated circuit (like a cell phone, or a disconnected laptop, handheld radio, electronic calculator, electronic watch, ... ), the "ground" is often the point where the voltage is at its minimum.

For an isolated circuit with a battery, unless otherwise specified, the + pin of the battery is Vcc and the - pin of the battery is the ground.

"ground" or "gnd" is kind of a loose term. In an engineering design office the convention may be used that gnd is traceable to an actual ground rod driven into the earth. If it is simply a junction point where the voltage is defined as zero it is called "common" or com. Less chance of confusion that way.

Thank you vanderghast and Foxx. After each of your replies, I proceeded to craft one of the two zener voltage regulator circuits I desired, tying the negative pole of the "Voltage Source" directly to "GND (G)." When finished, I inserted the "Digital Probe" throughout the circuit and clocked "Simulate." Unfortunately, no wire - not even the positive "Voltage Source" wire returned a single voltage; "Run DC Solver" failed to execute and auto-shutdown. Wishing to save my work so I could add it to dedicated thread to seek feedback, I encountered a "Cannot save without an active CircuitLab membership" prompt. Now I'm simply out of luck altogether.

To share simply, I have two separate zener voltage regulator circuits I am seeking an educated mind to either (1) confirm as being equivalent or (2) provide guidance on how to make them equivalent. Alas, I cannot find ANYWHERE online - including MIT's "free" online question submission forum - in which an engineer will assist. If anyone here can refer me to another online resource that will help, my entire work team would be most grateful. Thank you.

Note that the source, here V1, must supply a voltage greater than the Zener voltage, else, the Zener diode will stop the current through it.

Technically, to avoid excessive lost in heat through the resistors, you could design them to allow just a little bit more than 1 mA through them. As example, it would be better, for R1, to obey: 12 volt = 5.1 volt (zener) + R1 * 0.001 amp, giving R1 less or equal to 6.1 kohm.

Typo: it is 6.9 kohm, not 6.1.

I appreciate your motivation and effort on this subject, vanderghast; however, I literally have two separate zener voltage regulatory circuits (built using Electronics Workbench/National Instruments multiSIM 8 software) I am seeking feedback on. Thanks to your guidance, I can build both on Circuit Lab; unfortunately, I cannot save them to attach in a thread for outside review. If no additional ideas populate here, this, too, will become a lost opportunity to receiving the expertise my team is requesting.

I have used Circuit Lab for some time now and found it is well worth the cost even for hobby plus some work you might call "pro bono". I only wish it had been available when I made living at this stuff. Based on my experience it would be well worth while for you to get a membership.

If I were remaining in my current position long-term - true - I'd find value in a resource like this. However, I'll be transitioning out in less than a year; where I'd headed won't have need for creating circuit simulations.

This zener question is the only doubt we have on our team - once we resolve it, we'll be squared away.