Timing of different phases in an ignition circuit

摘要

The need of implementing a second local oscillator beside the drive oscillator, for timing the different phases of the starting process of a half-bridge or bridge stage driving an external load such as a fluorescent lamp, is avoided by employing a timing counter to count the number of oscillations produced by the drive oscillator and a digital-to-analog converter for controlling the frequency of oscillation of the drive oscillator. <IMAGE>