An open-source UFBGA µ-board for wearable devices

Area of Science:

• Electrical Engineering
• Embedded Systems Design
• Wearable Technology

Background:

• Development of compact, low-power microcontrollers is crucial for the proliferation of wearable devices and cyber-physical systems.
• Existing microcontroller breakout boards often lack the miniaturization required for seamless integration into wearable prototypes.
• The need for accessible, open-source hardware platforms for educational and research purposes in electronics is growing.

Purpose of the Study:

• To design and develop an open-source, ultra-low-sized microcontroller breakout board.
• To enable the creation of wearable and cyber-physical prototypes using a specific low-power microcontroller.
• To provide a cost-effective solution for educational electronic projects, particularly in Instrumentation and Assistive Technology.

Main Methods:

• Utilized the ATtiny20-CCU Microchip AVR microcontroller, an 8-bit, low-power device.
• Employed the Atmel Tiny Programming Interface (TPI) for programming, bypassing the need for a bootloader.
• Designed and manufactured a miniaturized Electroless Nickel-Immersion Gold (ENIG) Printed Circuit Board (PCB) leveraging Ultra Fine-pitch Ball Grid Array (UFBGA) packaging.

Main Results:

• Successfully developed a functional open-source, ultra-compact microcontroller breakout board (15.5 x 13 mm).
• Demonstrated the feasibility of programming the ATtiny20-CCU using TPI without a bootloader.
• The board is suitable for wearable instrumentation and cyber-physical prototypes, with potential for educational applications.

Conclusions:

• The developed µ-breakout PCB board offers a highly compact and cost-effective solution for wearable instrumentation.
• This open-source hardware facilitates advancements in assistive technology and educational electronics.
• The design aligns with the emergent needs of Society/Industry 5.0, emphasizing miniaturization and accessibility.