A Calibration-Free Synthesizable Odometer Featuring Automatic Frequency Dead Zone Escape and Start-up Glitch Removal

This paper presents a synthesized version of the silicon odometer aging sensor for measuring the frequency degradation caused by device degradation mechanisms in high volume semiconductor products. In the design, three ring oscillators (ROSCs) composed of inverter, NAND, and NOR gates are implemented in register-transfer-level (RTL), with the ability to be stressed in an AC or DC stress condition. The new odometer has product level features such as calibration-free operation, automatic frequency dead zone escape, and start-up glitch removal. The odometer verilog code was synthesized and automatically placed-and-routed in three different technologies using standard ASIC design tools. As a proof of concept, we show aging data collected from a 65nm test chip with 12 synthesized odometer instances. The open-source RTL files and testbench of the synthesizable odometer can be downloaded from https://github.com/reliability-research/odometer.