High Temperature (230 °C) Isolated Power Supply
This paper discusses the development of a high temperature (i.e., 230 °C ambient) 100V–300V/15V 20W isolated power supply. The power supply is implemented using Silicon-Carbide (SiC) power switches, high-temperature silicon on insulator (HTSOI) control circuitry, as well as custom high temperature magnetics and packaging technology. The heart of this power supply is a custom-built PWM controller. The controller was built utilizing HTSOI component, which operate at temperatures as high as 300 °C. The developed power supply targets high ambient temperature environment applications and includes features such as housekeeping power supply, soft-start and under-voltage lockout. The power supply is packaged using a multi-chip module (MCM) packaging approach. A single layer power substrate and a multiple layer control substrate are used. Bare die devices are utilized to save space, reduce parasitic impedances, and increase temperature of operation and reliability. This paper provides details on the electrical and thermal design as well as fabrication and characterization of the power supply. Additionally, results of the full characterization of this power supply are provided; this includes temperature testing up to 230 °C, efficiency results, load transition behavior, output ripple, etc.