Operation of fluorescent lamps from batteries using pulsed power transistors and autotransformers

A robust transistor configuration is described for high-frequency pulse operation of fluorescent lighting, eliminating the need for clamping diode wastage of the turn-off spike energy, and facilitating the use of ferrite yoked autotransformers to couple the transistors to the lamps. Significant improvement in light output, for the same electrical power input, is gained by utilizing autotransformers instead of separated primary and secondary windings. The robust transistor configuration has facilitated the exploitation of the highest efficiency advantages of the pulsed autotransformer by removing the danger of turn-off voltage spike damage to the semiconductor device structures, which would be a hazard for unsnubbed conventional Darlington or gate turn-off thyristors.<>