GND in a DC circuit with circuit board

Question

I wonder a question. Let's say I use a circuit board in a project (the left hand side on image below, not the Verabod), and I want to solder a circuit on it.

For example, I want to use the circuit below, the DC/DC converter using NE555: How should I do with the GND? I mean in this "portable" circuit board.

Should I just lead those line connecting to GND to an empty circuit board track?

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I just have a research online and I find out something. So, does it mean the circuit 1 is equal to circuit 2? Which all Ground is connected back to the negative pole of battery.

(1)

(2)

Answer 1

Based on the picture in the question you have a PCB stripboard such as following

So I would layout the components such that all the pin connected to ground use one strip. Also Circuit 1) and Circuit 2) are both the same with respect to GND.

I suggest that you look at fritzing. They have tools that will help you layout the board on CAD before you start soildering. Below are some links that might be of interest to you.

References:

• Fritzing Tutorial Stripboard
• Fritzing
• How to make traces on an universal PCB?

Answer 2

To understand circuits you need to know that there are no absolute voltages. All voltages are properly called potential differences, i.e. the difference in potential between two points. Ground is a conventional name for the point from which all other voltages are measured. (Confusingly, it's also a name for a point on the circuit which is connected to the ground you stand on, but that's not relevant here.)

So you need to:

• Connect all the GND points on your circuit together
• Connect it to the GND in whatever circuits are connected to Vin and Vout.

In your particular case, that second point means connect GND to the negative terminal of the battery, as in your second circuit. Note that you've missed a ground in the top right though, that also needs connecting.