Very Small too, A 2A continuous duty buck mode CV device that commonly sells for 2 or 3 dollars is 20 X 42 X 12 mm. The CV-CC modules at the same current are about twice the size and sell for less than 5 dollars... Both in single quantities...
A 25 watt heat sink is frequently more money... W/O any parts.
The first one I mentioned is one I use frequently as a pre-regulator for the discarded printer power supply power modules I find and or buy from the local "Thrift" stores... A 30V .7A HP Printer supply is 21 watts of power, and here in the US already UL approved.. safe..
This is for me 5V @ 4A output or 7.5V @ 2.5A, An Ideal input voltage for an Arduino board as the voltage (7.5V) is Ideal for the AMS1117-5.0 regulator on any of the Uno, Mega and Leonardo boards I use.... When I designed my own.... back when I worked for a living were even smaller... An MCP16301 will produce 500 mA from a 16.5 V input and is in an SOT-23-5 case.. I use one of them to support 2 Sure Electronics 3208 scrolling displays that use the Holtek HT1632 IC with 4, 8 X 8 5mm red matrix LED displays Each...
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