In this project, we will explore and develop analog/mixed-signal IC for implantable neural stimulation. We want to tackle the miniaturization of ultrasound electronics for efficient driving, readout and processing, enabling new horizons of experimental use and applications. Most of the ultrasound stimulators are developed for the use outside the body, so form factor and power consumption are not constrained. But for ultrasound stimulator that can be placed close to the nerve bundle, low energy consumption and small form factor are extremely important due to the heating constraint and possible nerve damage. CMOS ASIC can directly integrate with MEMS-based ultrasound transducer (e.g. pMUT). In this project, we also want to explore ASIC-pMUT integration to boost the efficiency and reduce physical size and costs. In this project, we will study the ASIC requirements of implantable ultrasound stimulation. We will also design and implement the pulser, beamformers etc circuits. If the development fits to the project need, there is also option to tapeout the circuit.