thermally compensated precision voltage reference

This internship at Logitech Europe SA, carried out within the EPFL Innovation Park in Lausanne, focused on the design, simulation, and implementation of a thermally compensated precision voltage reference intended for the KOSMOS emulator platform. The work began with an in-depth review of the existing voltage reference architecture, followed by a comparative study of high-stability components such as the LTZ1000, LTC6655, and MAX6325. After identifying thermal drift as the main source of precision degradation, several analog thermostat solutions were explored, ranging from simple hysteresis-based on/off control to proportional–integral (PI) and full proportional–integral–derivative (PID) control loops. Using LTspice simulations, thermal feedback models, and frequency-domain stability analysis, optimized architectures were developed and validated experimentally. The transition from breadboard prototypes to a custom multi-layer PCB revealed real-world challenges of thermal coupling, overshoot, and integral saturation, which were mitigated through iterative tuning and design refinements. Ultimately, the project resulted in a compact and robust PCB-integrated PID compensation circuit capable of achieving sub-degree stability, with potential improvements identified for future iterations. This work combined theoretical analysis, circuit simulation, and hands-on experimentation, while providing practical insights into precision analog design and control in a collaborative engineering environment.