USB-C PD Multi-Rail Power Supply

Configurable USB-C Power Delivery implementation using the CYPD3177 controller with three integrated buck converters providing regulated 12V, 5V, and 3.3V outputs.

Built as a versatile bench power supply for testing projects requiring multiple voltage rails from a single USB-C source. Demonstrates proper PD negotiation protocol and stable multi-rail voltage regulation.

The CYPD3177 controller handles PD negotiation with configurable $V_{min}$, $V_{max}$, $I_{sink}$ coarse, and $I_{sink}$ fine settings. Safe 5V fallback ensures basic power even if PD negotiation fails.

Key Features

• USB-C Power Delivery input (supports up to 20V profiles)
• Configurable voltage and current negotiation
• Three independent buck converters (3A each):
• 12V output @ 3A
• 5V output @ 3A
• 3.3V regulated output @ 3A
• Safe 5V fallback output
• Compact design suitable for bench use