SparkFun BabyBuck Regulator Breakout - 5V (AP63357)

The SparkFun 5V BabyBuck Regulator Breakout is a compact and efficient power regulator, featuring the AP63357 from Diodes Inc. This 3.5A synchronous buck converter has a wide input voltage range of 3.8V to 32V. With a fully integrated 74mΩ high-side power MOSFET and 40mΩ low-side power MOSFET, this unit provides a high-efficiency step-down DC/DC conversion.

This BabyBuck regulator is a simplified version of SparkFun's buck regulator boards. It is designed to deliver a regulated 5V output from a 6 to 32V input voltage range. The board includes a high-voltage EN (enable) control pin that is rated up to 32V. A small copper pad on the back of the board is available for attaching a heat sink to dissipate excess heat. The entire assembly fits on a compact 16mm x 13.2mm board layout, with only four PTH pins required for connecting input and output power.

The SparkFun BabyBuck regulator can output up to 3.5A, but due to thermal constraints, a maximum of 3A is recommended without sufficient active cooling. For a larger, full-feature version of this board, consider the SparkFun Buck Regulator Breakout - 5V (AP63357).

The BabyBuck Board includes:

• 16mm x 13.2mm PCB layout
• Four 2.54mm spaced PTH pins: VIN (Power In 6V to 32V), GND (Common Ground), VOUT (Power Out - Regulated 5V), EN (Enable - Pull high to enable the power output)
• 12.7mm x 15.24mm Plated copper pad for heat sinks

The AP63357 features:

• 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) with 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 including Undervoltage Lockout (UVLO), Output Undervoltage Protection (UVP), Cycle-by-Cycle Peak Current Limit, and Thermal Shutdown

For more information, refer to the following documents:

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