Dynamic Thermal Voltage Adaptation for LED Branches in Automotive Applications Martínez Pérez, José Ramón Carvajal Rodríguez, Miguel Ángel Santaella, Juan José Escobedo Araque, Pablo López Ruiz, Nuria Martínez Olmos, Antonio Automotive lighting LED Temperature This research was funded by Valeo-UGR Chair. P. Escobedo thanks project IJC2020-043307-I funded by MCIN/AEI/10.13039/501100011033 and by “European Union NextGenerationEU/PRTR”. This paper presents a novel technique for thermally compensating the power output of a DC-DC converter that supplies automotive lighting/signaling systems with multiple LED branches. The method ensures stable bias voltage for the current drivers controlling each branch, maintaining consistent power consumption across a wide temperature range. This issue has been minimally addressed in existing literature, providing few solutions which are too complex for industrial production. The approach proposed is simple and involves incorporating a temperature-sensitive thermistor into the DC-DC converter’s control loop, enabling the output voltage to adjust with ambient temperature. Different control loop configurations are explored, demonstrating that a simple resistor-thermistor network can approximate the desired voltage response under diverse thermal conditions. The power dissipated in the current drivers is kept within a controlled range, improving system efficiency and reducing heat loss. Additionally, it minimizes the need for additional current drivers, lowering the cost of these systems, improving battery life of the DC-DC converter, and decreasing CO2 emissions. For the case studies analyzed, an optimized configuration with appropriate resistor values and thermistor models achieves a 75% relative reduction in power dissipation by the current driver and a 50% improvement in the relative efficiency of the LED branch system. 2025-09-05T11:21:08Z 2025-09-05T11:21:08Z 2025-09-01 journal article Martínez-Pérez, J.R.; Carvajal, M.A.; Santaella, J.J.; Escobedo, P.; López-Ruiz, N.; Martínez-Olmos, A. Dynamic Thermal Voltage Adaptation for LED Branches in Automotive Applications. Sensors 2025, 25, 5392. https://doi.org/10.3390/s25175392 https://hdl.handle.net/10481/106109 10.3390/s25175392 eng open access MDPI