Static and Dynamic Characterization of a Monolithic Integrated Temperature Sensor in a 600 V GaN Power IC

Abstract:
This paper presents a characterization of monolithic integrated temperature sensors in a 600 V GaN-on-Si Power IC for half-bridge converters, by performing static and dynamic measurements. The static characterization is realized by steady-state temperature evaluation, while for dynamic characterization several power steps are applied to either one or both high-side and low-side transistors. Compared to a similar half-bridge, which uses external platinum resistors as temperature sensors, the superior performance of the integrated sensors regarding response time (30-fold decrease) is shown. With the integrated temperature sensors in both half-bridge transistors, asymmetric power loss and temperatures were measured. Furthermore, on-line temperature measurements are shown in a resonant-switching half-bridge, where a 0.25 K temperature change was measured after a 50 ns dead-time variation. During continuous hard-switching operation of two GaN power ICs in a half-bridge at 200 V input, 3 A output with up to 99% efficiency and 536W output power, the effect of output voltage variation between 20 V and 180 V on high-side and low-side device temperature increase was measured in real-time.