The cross-application of PCBA and bioelectronics technology has opened up a new field of intelligent medical and health monitoring, integrating flexible electronic manufacturing, biosensing, and data analysis to create high-performance, miniaturized, and biocompatible electronic devices. Unlike traditional PCBA used in consumer electronics, bioelectronic PCBA must balance biocompatibility, signal sensitivity, and mechanical flexibility, adapting to the complex physiological environment of the human body and meeting the needs of long-term contact or implantation. With the continuous advancement of technologies such as organic electrochemical transistors (OECTs) and flexible printed circuit boards (FPCBs), PCBA has become an indispensable core component in wearable health monitors, implantable medical devices, and point-of-care testing equipment, promoting the transformation of medical care from "treatment-oriented" to "prevention-oriented".

In wearable bioelectronic devices, PCBA's cross-application is mainly reflected in the integration of flexible circuits and biosensing technologies. Flexible PCBs (FPCBs) made of polyimide (PI) or polyester (PET) are lightweight, bendable, and comfortable to wear, which can conform to the body's natural movements without affecting daily activities. These FPCBs are integrated with biosensors to detect physiological indicators such as heart rate, blood glucose, body temperature, and wound exudate biomarkers in real time. For example, soft bioelectronics embedded with self-confined tetrahedral DNA circuits (SCTD) use PCBA as the carrier to monitor inflammation-related proteins in chronic wounds, with the detection limit reduced by an order of magnitude and excellent mechanical stability (only 3% variation after 1000 bending cycles). In addition, rigid-flex PCBs are widely used in compact wearable devices, combining the mechanical stability of rigid PCBs with the flexibility of FPCBs, reducing the need for external cables and connectors, and miniaturizing the overall device size.

In implantable bioelectronic devices, PCBA's cross-application faces more stringent requirements for biocompatibility and reliability. Implantable PCBs must be made of biocompatible materials such as titanium alloy, stainless steel, or ceramic-filled PTFE to avoid immune rejection when in contact with human tissues for a long time. For example, pacemakers and neurostimulators use rigid PCBs as the core control module, which provide robust mechanical support and stable electrical performance, ensuring accurate delivery of electrical signals to regulate physiological functions. HDI (High-Density Interconnect) PCBs are crucial for miniature implantable devices, using microvias, blind and buried vias, and fine-line technology to integrate more functions in a compact volume, such as in miniature neurostimulators that require high performance in extremely small spaces.

The cross-application of PCBA and bioelectronics technology also relies on the innovation of manufacturing processes and signal processing capabilities. Inkjet printing technology combined with FPCB manufacturing has realized the rapid and low-cost production of flexible OECT devices, which can amplify weak biosignals at extremely low power, making them ideal for in-sensor computing applications in bioelectronics. PCBA integrated with AI signal processing modules can filter and analyze the collected physiological data in real time, providing accurate health assessment and early warning. However, there are still challenges in this cross-field, such as improving the long-term stability of PCBA in the human body, reducing biofouling, and lowering manufacturing costs. With the continuous breakthrough of materials science and manufacturing technology, PCBA will further promote the miniaturization, intelligence, and portability of bioelectronic devices, bringing new changes to medical health and life science research.