The SparkFun 3.3V Buck Regulator Breakout features the AP3429A from Diodes Inc., a 2A step-down DC-DC converter with an input voltage range of 2.7V to 5.5V. This full-size, 1in. x 1in. version of our buck regulator boards is configured to provide a regulated 3.3V output (from a 3.9 to 5.5V input voltage range), which is controlled by an EN (enable) pin. To dissipate excess heat, a 0.6in. x 0.5in. copper pad is provided to attach a heat sink to the bottom of the board.
As a full-size buck regulator breakout, additional options for connecting input and output power are available. There is a pre-assembled screw terminal for a non-permanent connection, the option to solder on a barrel jack for an external power supply, and five PTH pins to create a more permanent installation. Our full-size buck regulators also come with a red, power indication LED that light up when the power output is enabled. This board has four mounting holes compatible with 4-40 hardware.