SparkFun Buck Regulator Breakout - 5V (AP63357)

The SparkFun 5V Buck Regulator Breakout is a powerful tool that boasts an AP63357 from Diodes Inc., a 3.5A synchronous buck converter with an expansive input voltage range of 3.8V to 32V. This versatile piece of equipment also features a fully integrated 74mΩ high-side power MOSFET/40mΩ low-side power MOSFET, providing a high-efficiency step-down DC/DC conversion.

The SparkFun Buck Regulator Breakout is configured to provide a regulated 5V output from a 6 to 32V input voltage range. This makes it an ideal choice for various applications where a steady and reliable power source is required. It also features a high-voltage EN (enable) control pin that is rated up to 32V. To help manage heat, a small copper pad is located on the back of the board where a heat sink can be attached if needed.

This full-size buck regulator breakout offers several options for connecting input and output power. It includes a pre-assembled screw terminal for non-permanent connections, the option to solder on a barrel jack for an external power supply, and five PTH pins for a more permanent installation. The breakout also comes with a red power indication LED that lights up when the power output is enabled, and two mounting holes compatible with 4-40 hardware.

The AP63357 is rated up to a 3.5A output, however, users should expect a maximum of 3A due to thermal constraints. The boards can output 3.5A but would require a sufficient amount of active cooling. For smaller, minimalistic versions of buck regulators, consider the SparkFun BabyBuck regulators.

The SparkFun 5V Buck Regulator Breakout comes with a variety of features including:

• 2.54cm x 2.54cm PCB layout
• Three power input/output options:
  • Pre-assembled 4-pin screw terminal
  • Five 2.54mm 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
• 1.27cm x 1.52cm Plated copper pad (for heat sinks)

The AP63357 features include:

• 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