Half-bridge Driver Chip Analysis And Design

Half-bridge circuits are widely used in ballasts,PWM motor drivers and DC-AC converters. Integrated half-bridge drivers have the advantages of smaller,more robust and more effective. There are several such ICs at present such as IR2153 of IR Company and L6569 of ST Company. These ICs have the same characters that the high and low voltage circuits are integrated in one chip, thus advanced fabricating technology and well-designed circuits are needed.This paper talks about the key technology of designing circuits based on basic half-bridge structure. In this design, high-voltage level-shifting structure is improved and a novel robust structure is realized. What is more, a high side pulse filter is designed based on logic filter concept. The testing results proves that this IC could exhibit its function in testing condition, and it can ignite the fluorescent light, though some problems still exitst in some sub-circuits. The schematic design and layout design of these circuits, as well as the failure reasons, are studied deeply. At the end, some suggestions to improve the performance of the IC are given.This paper tries to talk about three aspects of half-bridge driver circuit, including physical and system structures and circuits design. And readers could clearly understand the whole structure and details of the IC without being limited by sub-circuits design. And we also regard the completed function as the first goal but not the design and test of sub-circuits design. However, circuit design is the basis to achieve final goal, so sub-circuits are also analyzed in this paper. And efforts are made to improve the performance of the circuits based on the special fabrication technology.