This work presents a compact, self-powered pressure sensor based on a triboelectric nanogenerator (TENG), which is developed for total knee replacement (TKR) implants. Unlike conventional bulky and inefficient systems with separate attenuators and signal processing units, this design seamlessly integrates a pressure sensor within an energy-efficient energy harvesting (EH) circuit. The system features a bidirectional, high-voltage (HV) four-input buck converter with a newly proposed HV protector, enhancing EH efficiency across four different input voltages. The converter achieves a maximum end-to-end efficiency of 79.21%. Additionally, the pressure-sensing circuits offer accurate readouts by sampling the HV open-circuit voltages (VOC) from TENGs using a VOCsampler without the need for an attenuator. Compared to state-of-the-art solutions, this work not only achieves competitive energy harvesting performance but also introduces, for the first time, a fully integrated pressure-sensing function.

A hybrid high-voltage regulating charge pump is proposed for point-of-care electrokinetic concentration chip applications. The hybrid charge pump is composed of three cascaded sub-pumps. High efficiency, minimized area, wide output current range, and high regulated output voltage are achieved by selecting charge pump architectures that provide high voltage conversion gain with less number of stages. The proposed charge pump is designed and fabricated in 180 nm BCD process. Simulation results show that the proposed system provides a maximum efficiency of 48.26%, while providing a maximum output voltage of 65 V.

We present an energy-efficient, scalable neural stim-ulation IC with adaptive dynamic voltage switching, which can be applied to cochlear implant (CI) systems. The stimulation IC generates three different voltage outputs by operating a single-inductor multiple-output (SIMO) boost converter, while an adaptive dynamic voltage switching (ADVS) block selects an appropriate supply voltage for each stimulation channel among those SIMO outputs. The SIMO boost converter is designed to operate over a wide range of its input, which is the rectifier output of the wirelessly powered CI system. The ADVS control as well as the stimulation amplitude control are performed remotely by an external sound processor (SP) of the CI system in real time. For the ADVS operation, the compliance voltage of each stimulation channel is monitored to be used as an input signal for switching to the appropriate supply voltage for the corresponding stimulation channel. The dynamic voltage switching operation is carried out in sub-us, The stimulation IC with ADVS is implemented using a 180-nm BCD process, and its operation and performance are verified through post-layout simulations. When applying a real audio input using decoded data from a prototype SP, the proposed stimulation IC with ADVS demonstrates 36.6% energy saving compared to the conventional stimulation IC.