POWER SUPPLY AND ELECTRONIC BALLAST WITH AUXILIARY PROTECTION CIRCUIT

摘要

An arrangement (10) comprises a front-end circuit (100), a back-end circuit (200), and an auxiliary protection circuit (300). Front-end circuit (100), which typically includes an EMI filter and rectifier circuitry, has first and second input connections (12,14) for receiving a conventional source of AC voltage (20). Back-end circuit (200), which typically includes power factor correction and inverter circuitry, is coupled to front-end circuit (100) and a load (30) such as one or more gas discharge lamps. Auxiliary protection circuit (300) is coupled between front- end circuit (100) and back-end circuit (200). During operation, auxiliary protection circuit (300) protects back-end circuit (200) from any malfunction or damage that may occur due to a line-sag condition or due to a phase-to-phase miswiring condition. Additionally, auxiliary protection circuit (300) significantly reduces the peak inrush current that is experienced by arrangement (10) following initial application of AC power.