Smart Biofeedback Earbud Achieved by SiP with 3D Composite Polymer Package

The world’s first smart in-ear bud packaged in polymer is presented in this paper. This in-ear bud is capable of detecting ECG (electrocardiography) signal, heart rate, as well as body temperature, from human ear canal. The bud is designed to be connected to a typical wireless ear-set, which transmits signal through Bluetooth. It is assembled with advanced packaging technologies, including SiP (system in package) module for system board miniaturization, flexible substrate for conforming to the 3D structure, and molding with composite polymer material by multiple injections for bio contact. The composite material is liquid in raw material form, yet elastic and solid after vulcanization. This material is heterogeneous integrated, such that it encapsulates the functional active and passive parts, allows the bio signals to be detected. The earbud conforms to the exterior ear canal, and is friendly to sensitive human skin.In this paper, this smart earbud is connected to a wearable Bluetooth docking box, and live demo is performed to transmit the detected biofeedback signal to an App on an android phone or PC. The user plugs this smart earbud into the left (heart side) ear canal and touching the metal electrode of BT docking by the left hand finger. Biofeedback signal of stable and repeatable PQRST wave, heart rate, and body temperature are detected and sent, and results are shown successfully. The test data of user trial is compared with another set of data from a leading consumer watch, tested by the same users. Very similar characteristics of the waveforms from the smart earbud, and those from the benchmark devise, are observed. It is expected that this innovative smart earbud can be integrated into similar consumer wearable electronics, which can provide real time, accurate, and convenient way of bio sign monitoring for the consumers.