The Boeing Company
Stabilizing the startup behavior of ring oscillators

Abstract:

A system for providing security in a computer system is provided. The system includes a ring oscillator including a plurality of logic gates connected in a ring configuration. The system also includes logic circuits to start the ring oscillator by a ring-enable signal and a clock signal provided to a clock input of at least one controlled logic gate of the plurality of logic gates. The clock signal controls the at least one controlled logic gate and thereby synchronizes the ring oscillator to the clock signal. The clock signal is provided to the clock input for a predetermined warm-up duration, and thereafter, the logic circuits restart and operate the ring oscillator without the clock signal.