# SparkFun Buck Regulator Breakout - 5V (AP63357)

**Type:** Product page · **SKU:** COM-21255 · **Brand:** [Sparkfun](https://core-electronics.com.au/brands/sparkfun-australia)
**Page:** https://core-electronics.com.au/sparkfun-buck-regulator-breakout-5v-ap63357.html ([markdown](https://core-electronics.com.au/sparkfun-buck-regulator-breakout-5v-ap63357.html.md))

The SparkFun Buck Regulator Breakout - 5V features the AP63357, a 3.5A synchronous buck converter with a wide input voltage range of 3.8V to 32V...

## Pricing

- **Price:** $14.95 (inc GST) — $13.59 AUD, exc GST
- **Quantity discounts:** 5+ $13.18 (exc GST) · 25+ $12.91 (exc GST) · 100+ $12.36 (exc GST)

## Availability & dispatch

- Available with a lead time — expect dispatch between Sep 01 and Sep 07.

## 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 74mO high-side power MOSFET/40mO low-side power MOSFET provides a high-efficiency step-down DC/DC conversion.

This full-size, 1in. x 1in. version of our [buck regulator boards](https://www.sparkfun.com/categories/tags/buck-boost) is configured to provide a regulated 5V output 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](https://core-electronics.com.au/search/?q=119) for an [external power supply](https://www.sparkfun.com/categories/308), 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 and two mounting holes compatible with [4-40 hardware](https://core-electronics.com.au/search/?q=4-40).

Check out our [BabyBuck regulators](https://www.sparkfun.com/categories/tags/babybuck) and the [SparkFun BabyBuck Regulator Breakout - 5V (AP63357)](https://core-electronics.com.au/search/?q=21256), for the smaller minimalistic versions of our buck regulators.

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

 [Get Started with the SparkFun AP63357 Buck Regulator Breakout Hookup Guide](https://docs.sparkfun.com/SparkFun_Buck_Regulator_AP63357DV-7)### Features

**Buck Board Features:**

- 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](https://core-electronics.com.au/search/?q=119) *(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 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)
    - 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 5M? 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

### Documents

- [Schematic](https://core-electronics.com.au/attachments/localcontent/schematic-Buck5V_1018136e01a.pdf)
- [Eagle Files](https://core-electronics.com.au/attachments/localcontent/eagle_files-Buck5V_18321e03c3a.zip)
- [Board Dimensions](https://core-electronics.com.au/attachments/localcontent/dimensions-Buck5V_22246ff802c.pdf)
- [Datasheet](https://core-electronics.com.au/attachments/localcontent/AP63356-AP63357_16993a82757.pdf) (AP63357)
- [Product Page](https://www.diodes.com/part/view/AP63357/) (AP63357)
    - [Technical Documentation](https://www.diodes.com/part/view/AP63357/#tab-details)
- [Diodes Technical Support Page](https://www.diodes.com/about/contact-us/technical-support/)
- [GitHub Hardware Repo](https://github.com/sparkfun/SparkFun_Buck_Regulator_AP63357DV-7)

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/C/O/COM-21255-1.jpg)