SparkFun Buck Regulator Breakout - 3.3V (AP3429A)

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.

Features:

Buck Board:

• 1in. x 1in. PCB layout
• Three power input/output options:
  • Pre-assembled 4-pin screw terminal
  • Five 0.1in. spaced PTH pins
  • Four plated slots for a DC barrel jack (input only)
• Power connections:
  • VIN - Power In (3.9V to 5.5V)
  • GND - Common Ground
  • VOUT - Power Out (Regulated 3.3V)
  • EN - Enable (Pull high to enable the power output)
• Red, power LED indicator
• 0.5in. x 0.6in. Plated copper pad (for heat sinks)

AP3429A:

• VIN: 2.7V to 5.5V
• VOUT: 0.6V to VIN
• 2A Continuous Output Current
• 90µA No-Load Quiescent Current
• 1MHz Switching Frequency
• Protection Circuitry
  • Undervoltage Lockout (UVLO)
  • Input Overvoltage Protection
  • Over Current Protection
    • Cycle-by-Cycle Peak Current Limit
  • Thermal Shutdown (160°C/320°F)

Documents:

• Schematic
• Eagle Files
• Board Dimensions
• Hookup Guide
• Datasheet (AP3429A)
  • AP3428 Application Note
• Manufacturer's Product Page (AP3429A)
  • Technical Documentation
  • Diodes Technical Support Page
• GitHub Hardware Repo