There is provided a jitter detection circuit of a phase locked loop circuit, comprising a comparison circuit. Trenched field relief regions are arranged to deplete the intermediate drift region when the diode is reverse biased, so permitting a higher doping to be used for the intermediate drift region for a given breakdown voltage. A lighting system is located generally in the compartment and includes a power source, such as a battery set. A peak cylinder pressure and a corresponding crank angle are detected and captured during the combustion cycle. The end cap assembly includes a base, fluid port and handle which may optionally comprise an integrally molded structure. The adsorbing agent exhibits improved activity and stability, and at the same time, is capable of significantly improving the octane number of the product gasoline.