Multiple connections to power supply

Question

My son and I are making an amplifier from a board from Amazon that requires 9-26 V DC input. I have an old laptop charger and am wondering if I can connect more ancillary boards such as input selection or tone control boards using the one power supply. If so, what would the wiring look like for this? If not, can I connect multiple power supplies to the same AC input into the case we will build? What will the wiring look like for this, would it just be as simple as looping wires from the incoming AC cable to the different power supplies? Would they then be wired in parallel?

We're both just learning. My son is autistic and has shown a keen interest in all things HiFi and electronic so we are going to learn as we go on together.

Answer 1

A single power supply can be shared with multiple "loads" provided that

• All loads are tolerant of the voltage.

• Total load current is less than that able to be provided by the power supply.

Voltages:

You do not say what voltage the laptop charger provides.
The most common is 19VDC. They can also be 16V, 12V and "other".

In this case it is likely that most other loads would use a lower supply voltage - typically 12 VDC. 5VDC is also common.
If so, using two or three supplies may be better.

The supplies should have their negative outputs joined.

Sourcing power supplies:

Used power supplies for various items of consumer equipment are extremely commonly available - often at no cost. Output plugs can be used, or they can be cut off and the wires terminated in some other manner.

Choose supplies with electonic regulators - these are now almost the only ones sold, but older ones often used transformers. Transformer based supplies are usually far heavier per size and have lower power ratings per size. The reason not to use them is that most have poor voltage regulation. A 12 VDC rated supply may output 14 or 16 or more volts under light or no load. This can be catastrophic for some equipment.

AC commoning.

You could "loop wires from the AC input.
As you are new to this area I suggest that it would be safer to use existing mains cables and a "power distribution board", with each supply either plugging into the distribution board directly, or via a premade power cable. This may look a little "Heath Robinson" inside the case - but would not be discernible from outside the case.