Buck Regulator Breakout – 5V (AP63357) Sparkfun Electronics

DESCRIPTION

The SparkFun 5V Buck Regulator Breakout features the AP63357 from Diodes Inc., a 3.5A synchronous buck converter with a wide input voltage range of 3.8V to 32V. The fully integrated 74mΩ high-side power MOSFET/40mΩ low-side power MOSFET provides a high-efficiency step-down DC/DC conversion.

This full-size, 1in. x 1in. version of the buck regulator boards is configured to provide a regulated 5V output (from a 6 to 32V input voltage range) and features a high-voltage EN (enable) control pin that is rated up to 32V. On the back of the board, a small copper pad is available to dissipate excess heat with a heat sink.

As a full-size buck regulator breakout, additional options for connecting input and output power. 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. The full-size buck regulators also come with a red, power indication LED that light up when the power output is enabled and two mounting holes compatible with 4-40 hardware.

Note: While the AP63357 is rated up to a 3.5A output, users should expect a 3A maximum with the boards due to thermal constraints. The boards can output 3.5A but would require a sufficient amount of active cooling.

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
  • Three plated slots for a DC barrel jack (input only)
• Power connections:
  • VIN – Power In (6V to 32V)
  • GND – Common Ground
  • VOUT – Power Out (Regulated 5V)
  • EN – Enable (Pull high to enable the power output)
• Red, power LED indicator
• 0.5in. x 0.6in. Plated copper pad (for heat sinks)

AP63357:

• VIN 3.8V to 32V
• 3.5A Continuous Output Current
• 0.8V ± 1% Reference Voltage
• 22µA Low Quiescent Current (Pulse Frequency Modulation)
• 450kHz Switching Frequency
• Supports Pulse Frequency Modulation (PFM)
  • Up to 86% Efficiency at 5mA Light Load
• Proprietary Gate Driver Design for Best EMI Reduction
• Frequency Spread Spectrum (FSS) to Reduce EMI
• Low-Dropout (LDO) Mode
• Power Good Indicator with 5MΩ Internal Pull-up
• Precision Enable Threshold to Adjust UVLO
• Protection Circuitry
  • Undervoltage Lockout (UVLO)
  • Output Undervoltage Protection (UVP)
  • Cycle-by-Cycle Peak Current Limit
  • Thermal Shutdown

RESOURCES

• Schematic
• Eagle Files
• Board Dimensions
• Hookup Guide
• Datasheet (AP63357)
• Manufacturer’s Product Page (AP63357)
  • Technical Documentation
  • Diodes Technical Support Page
• GitHub Hardware Repo