This project is a high-efficiency, multi-input Power Distribution Board designed to provide stable, low-noise rails for interchangeable high-performance modules. It serves as the primary power hub for my 24-bit Precision ADC and STM32H7S3 System-on-Module projects.
The system is engineered for maximum field flexibility, allowing a single instrumentation stack to be powered via laboratory bench supplies, USB-C PD sources, or mobile battery packs.
The board features a triple-redundant input strategy to support diverse operating environments:
- USB Power Delivery: Utilizes an MCP2221A-I/ST USB-to-I2C bridge to communicate with PD controllers and negotiate specific voltage profiles.
- DC Input: A standard barrel jack for 12V DC wall converters, ideal for stationary bench-top development.
- Battery Port: A dedicated high-current connector for Lithium-Ion/Polymer battery packs, enabling untethered mobile data acquisition.
At the core is the MCP19061-E/RTB, a Digitally Enhanced Power Analog (DEPA) controller.
- Integrated MCU Control: Combines the performance of an analog peak current mode controller with the flexibility of a microcontroller.
- Dynamic Regulation: Enables real-time telemetry and adjustment of output levels to match the requirements of the downstream load.
- Protection Circuitry: Hardware-level Under-Voltage Lockout (UVLO), Over-Voltage Protection (OVP), and thermal shutdown.
- 4-Way Power Bus: Features four precision power connectors to distribute clean rails to a stack of interchangeable boards.
- Noise Mitigation: Designed with localized LC filtering and optimized PCB return paths to ensure switching noise from the DC-DC stage does not compromise the 120dB SNR performance of connected ADC modules.
| Feature | Component / Specification |
|---|---|
| Main Controller | Microchip MCP19061 (Integrated MCU + PWM) |
| USB Interface | MCP2221A-I/ST (USB-to-I2C/UART Bridge) |
| Input Range | Negotiated USB-PD / 12V DC / Battery |
| Topology | Synchronous Buck-Boost Converter |
| Output Ports | 4x Interconnect Headers |
This board was developed to solve the "Power Bottleneck" in modular hardware design. By decoupling the power stage from the logic and sensing stages, the system achieves:
- High Modularity: The "Interchangeable Device" architecture allows for swapping analog front-ends or digital processing units without redesigning the power delivery network.
- Field Readiness: The seamless transition to battery power makes the entire instrumentation stack viable for real-world environmental and oceanographic data collection.
- Stability: Centralized regulation reduces ground loops and phase coherency issues common in multi-board "nest" wiring.