A Versatile Power Supply in Your Pocket——Come and Support It！

PocketPD is a compact, USB Type-C powered desktop power supply designed to be easily carried in one hand or even tucked into a pocket. Despite its small size, it is packed with advanced features that make it a powerful tool for both professionals and hobbyists. It offers a wide voltage range while maintaining safety and reliability. In addition to its basic functions, PocketPD includes an OLED display, a current sensor, and a banana plug output, making it compatible with standard devices like modern USB-C chargers or power banks. One of its unique features is the ability to act as a Power Delivery 3.0 profile tester, helping users verify compatibility and performance.

By utilizing the Programmable Power Supply (PPS) mode found in USB Power Delivery 3.0 and later versions, PocketPD allows users to directly access precise voltage and current levels from their charger, offering greater control and flexibility than traditional power supplies.

The designer aimed to create an open-source, user-friendly, and portable solution that meets real-world needs. With physical buttons and a clear OLED display, PocketPD is ready to use right out of the box—just plug in a compatible charger or power bank, and you're good to go. No complicated setup or software required. Its combination of multifunctionality, ease of use, and portability makes it a perfect addition to any toolkit, whether you're a seasoned engineer or a beginner exploring electronics.

Core Design

The core functionality of PocketPD is based on the Programmable Power Supply (PPS) mode introduced in 2015. This mode was originally developed to enhance battery charging efficiency in smartphones, allowing for precise voltage and current settings. As a result, it's ideal for use in desktop power supply applications. Many modern USB-C chargers and power banks, including popular brands such as Anker, Ugreen, Baseus, and CUKTECH, now support PPS. If you're unsure about your device’s compatibility, always check the manufacturer’s documentation before use.

Please note: The maximum voltage and current output of PocketPD depends on the connected USB Type-C charger and cable. The actual output will be limited by the lowest current rating of either the charger or the cable. For example, if your charger supports 5A but you're using a 3A cable, the maximum output will be capped at 3A. Similarly, the voltage range available on PocketPD is determined by the capabilities of the charger. Common ranges include 3.3V to 11V and 3.3V to 21V.

Features & Specifications

• Input: USB Type-C, PD 3.0 compliant
• Output: 0–20 V @ 0–5 A (adjustable)
• Modes: Constant Voltage (CV), Constant Current (CC)
• Display: 0.96-inch OLED screen
• Microcontroller: Raspberry Pi RP2040 Cortex M0+
• Protocol IC: AP33772 USB PD sink controller
• Safety Features: Short circuit, reverse current, fly-back diode protection
• Dimensions: 87 x 62 x 25.5 mm (3.43 x 2.44 x 1 in)
• Weight: 81 g (2.87 oz)

This project is currently being crowdfunded on CrowdSupply. You can find more information about PocketPD there, and we encourage you to support it if you’re interested in this innovative and versatile power supply solution.