Power Efficient High Temperature Asynchronous Microcontroller Design

There is an increasing demand for dependable and efficient digital circuitry capable of operating in high temperature environments. Extreme temperatures have adverse effects on traditional silicon synchronous systems because of the changes in delay and setup and hold times caused by the variances in each device’s threshold voltage. This dissertation focuses on the design of the major functionality of an asynchronous 8051 microcontroller in Raytheon’s high temperature Silicon Carbide process, rated for operation over 300ºC. The microcontroller is designed in NULL Convention Logic, for which the traditional bus architecture used for data transfer would consume a large amount of power. To make the design more power efficient, the bus architecture has been replaced with a more complex yet efficient MUX-based data transfer scheme. This change in the design architecture also allows for improved internal data transfer rates leading to an increase in overall circuit performance. Simulation results show that the designed Silicon Carbide microcontroller framework successful executes 8051 ISA instructions. Results from the MUX-based architecture show an overall decrease in power consumption of over two orders of magnitude when compared with its bus architecture counterpart. Also, the increased internal data transfer rates resulted in an overall performance improvement of 22.8%