Step 1: Gather Things You Need. Everythings you need are: - A piece of perf board (I marked the real size of perf board which needed) - 0.23$ for that full size perfboard. - A ruler. - A knife. - A MOSFET (I use IC 06N03LA which I recycle from an old computer) - 0.18$ - Soldering wire and a solder (I forgot to take a photo)
Most AC-DC power supplies and DC-DC converters have internal current-limiting circuits to protect the power device, and to some degree its load. The majority of over-current-protections include an automatic recover feature. In practice, the current-limit circuits typically start operating when the output current exceeds its maximum rating by 10 Therefore in this variable power supply circuit using 2N3055 transistor, the transformer being a 0 - 40 V, the output becomes variable right from 0.6 to 40 volts maximum, that's very handy indeed. For implementing the current control feature, T3 along with P1, R5 and R4 are involved. The value of R4 is specifically becomes responsible forThe reason your "2A power supply" didn't do the limiting is that it wasn't built with "continuous current limiting" as a feature. There exists power supplies that have this feature, but they are generally more expensive as it's usually harder to build that feature than either an unlimited power supply (that you can destroy by overloading it) or