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 200°C. Designing SoCs for reliable operation at high temperatures is a significant challenge, due to increased static leakage current, reduced carrier mobility, and increased electro-migration. 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 20×9 mm² chip implementing this design has been fabricated in 0.35 μm CMOS technology. The custom testing procedure showed the expected maximum operating frequency reduction from 38MHz at room-temperature to 30 MHz at 200°C, which illustrates the importance of an adaptable clock frequency under temperature variation. At 200°C, the maximum power dissipation at 3.3 V supply voltage was 1.2W and the idle state static leakage current was 3.4 mA. Silicon measurements proved that this design outperforms PowerPC based SoCs available in the high-temperature microcontrollers market which are not operational at temperatures above 125°C.