Miniaturized digital oven-control microsystem with high power efficiency and ±1.8ppm frequency drift

This paper introduces a digital pulse width modulation technique for MEMS oven-control system. The proposed method generates digital, pulse width modulated signals from analog signals produced by a proportional-integral-derivative controller. This technique, therefore, provides good digital properties, such as better design scalability and higher power efficiency. These advantages are confirmed with an oven-control system for a commercial 6-axis inertial measurement unit. As a result, the oven-control system is fabricated on a single printed circuit board measuring 42mm×42mm×10mm and the power efficiency is increased to 94.4%. The entire system shows ±1.8ppm frequency drift during a thermal-cycle test, from −40°C to 85°C with the rate of the change 1°C/min.