Simple 3 Amp Step Down Switchmode Regulator
Although this example is 5V, there are also 3.3V, 12V, 15V, and adjustable output versions (see attached datasheet).
Except for the Adjustable output version the same layout can be used for each.
Note: Pin 5 (which is grounded below) can also be used to switch the external loads on/off via a logic input e.g. 0v or 5V, for example an LPT port.
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