An integrated precision clock generator for implanted electronics with superior long-term stability

This paper presents the design, simulation, bench measurement and long-term reliability test results of a drift-resistant clock generator. Designed for applications at a stable body temperature with a lifelong operating expectancy, this clock design uses multiple design techniques to minimize the long-term performance degradation and results in a clock circuit with superior frequency stability. This design has been implemented on a commercial CMOS process and bench test results show the PSRR of this circuit is 0.25%/V. Long-term frequency drift data indicates that this clock generator has a less than 0.5% frequency drift over 100-year operating time at body core temperature.