FireBird: PowerPC e200 Based SoC for High Temperature Operation

PowerPC Architecture microcontrollers are commonly used in embedded applications. In this work we present FireBird, the first PowerPC based SoC for reliable operation beyond 200C. It is a significant challenge to design SoCs for reliable operation at high temperatures, due to increased static leakage current, reduced carrier mobility, and increased electromigration. To alleviate the consequences of high temperatures, this paper proposes to customize a PowerPC e200 based SoC by using a dynamically reconfigurable clock frequency, exhaustive clock gating, and electromigration-resistant power supply rings. A 20x9mm2 chip implementing this design has been fabricated in 0.35m CMOS technology. The custom testing procedure showed the expected maximum operating frequency reduction from 43MHz at room-temperature to 33MHz at 200C, which illustrates the importance of an adaptable clock frequency under temperature gradients. At 200C, the maximum power dissipation at 3.3V supply voltage was 1.75W and the idle state static leakage current was 0.2A. Silicon measurements proved that this design outclasses PowerPC based SoCs available in the high-temperature microcontrollers market which are not operational at temperatures above 125C.