Wide-temperature and extreme-environment electronics are crucial to future missions. These missions will not have the weight and power budget for heavy harnesses and large, inefficient warm boxes. In addition, extreme-environment electronics, by their inherent nature, allow operation next to sensors in the ambient environment, reducing noise and improving precision over the warm-box-based systems employed today.

Current sensing applications are key in motor and power supply control applications. As higher levels of integration in spacecraft systems are sought, it is desired to integrate high-voltage interfaces onto highly integrated “System-on-Chip” (SoC) components utilizing low-voltage CMOS (complementary metal–oxide–semiconductor) process technology.

A circuit for a capacitively coupled, level-shifting, high-voltage current sense for extreme environments is disclosed. This circuit uses custom, on-chip, high-voltage components using standard CMOS masks to enable a high-voltage switched-capacitor differencing amplifier. Low-temperature-coefficient components and temperature-compensated biasing enable extreme-environment operation. The ability to integrate this type of component into large-scale, mixed-signal systems is a crucial advantage.

Extreme-environment electronics are valuable to a number of disciplines, including military/aerospace, automotive, scientific research applications, and energy.

This work was done by Jeremy A. Yager, Mohammad M. Mojarradi, Bruce R. Hancock, and Tuan A. Vo of Caltech for NASA’s Jet Propulsion Laboratory. NPO-48542