Decade voltage regulation box

[Pexy]

Hy I was wondering if it's worth and if it would be usefull to build a decade voltage regulator box that you could change output voltage regulation for example 3,5,9,12V using n-way switch(n=number) and a few voltege regulating circuits.

 

[shrtrnd]

What is your amperage?
There are plenty of selectable wall-wart adapters available here in the States for cheap.
Unless this is some high amp application, and you just want to use it for low amperage circuits, I'd look around for the inexpensive pre-made selectable voltage regulators.

 

[Pexy]

What is your amperage?
There are plenty of selectable wall-wart adapters available here in the States for cheap.
Unless this is some high amp application, and you just want to use it for low amperage circuits, I'd look around for the inexpensive pre-made selectable voltage regulators.

It would be low voltages and for the amps im not so sure. I would use it to change fix voltages forom a fix voltages forom a computer PSU.

 

[hevans1944]

You can use a programmable three-terminal regulator, such as an LM338, and drive the programming terminal from a digital-to-analog converter to create a computer-programmable voltage output. Or use discrete transistors driven from logic-level outputs to select the output voltage:

Above schematic from TI datasheet for LM338.

 

[Pexy]

You can use a programmable three-terminal regulator, such as an LM338, and drive the programming terminal from a digital-to-analog converter to create a computer-programmable voltage output. Or use discrete transistors driven from logic-level outputs to select the output voltage:

Above schematic from TI datasheet for LM338.

Thanks I will look it up and see what would be the best option.