Generating + and -10V Power Supply?

Question

I am building a circuit that needs to operate on +10V and -10V DC, and of course, a ground connection. It should be good enough to deliver just 1 amp. If I use a 120V to 10V AC transformer along with a bridge rectifier and capacitors, I should expect around +-13V DC. I will then use regulators to get it down to the voltage I need. Here is a quick power supply I threw together.

^{simulate this circuit – Schematic created using CircuitLab}

Now, while this solution does work, I don't want a bulky transformer either internally nor externally of the device. Is there any easier way to do this that would work with either an AC or DC wall-power barrel connector? Or will I have to stick to this circuit to get the -10V? I'll stick close by to answer any questions you may have to help me come up with an ideal solution. Thanks!

Answer 1

Maybe buying a 24v AC - DC Power supply, and with a resistor ladder divide in half the voltage at the input, hence creating a virtual ground at 12V. But this 12 V will be the ground supply for your circuit.

For voltage stability you can put a 7812 to regulate +12v with respect to virtual ground, and a 7912 to regulate -12v with respect to virtual ground.

Answer 2

The connections on your bridge rectifier are completely backwards. You have AC from the transformer connected to the rectifier's + and - outputs and you have the DC outputs connected to the rectifier's AC inputs.

All the grounds in the circuit should be connected together.

Answer 3

The old solution was to use an AC output wall wart and two half-wave rectifiers to generate positive and negative voltages in the device. But half-wave rectifiers need 2x the amount of capacitance, and that takes up space.

You can use a switching wall wart that generates +/- 10V but that will need a special connector, and maybe hard to find.

If you want a standard wall wart and barrel connector, then a solution is to use a switching converter to convert the positive voltage into negative. That's a compact solution.

Answer 4

Your question is closely related to already discussed question. Please visit the following link How make a dual +-12V supply from a 24V SMPS