The Drive Control Chip Central Molecular Circuits For Electronic Ballast Design

With the development of Smart Power IC and the increasing demand of the non-polluting efficient power-saving energy, electronic ballast has been paid more and more attentions on. Compared with the traditional ballast, it has the advantage of less power dissipation, less weight, no flicker, no noise and capability of ignition on the low supply voltage. Since it was born, electronic ballast has been popularized in the developed countries. Despite of the later start and the lag of the microelectronic technology, it is still a long way to go in the industry. As the core technology of the electronic ballast, the control and driver ICs become the most important thing we can make effort to do together with the power devices.A high voltage half bridge driver with built in oscillator is discussed in this paper. This Smart Power IC can be fabricated by normal CMOS process. Some details of the design, layout, tape-out and test are described in the main text. The device has a built-in oscillator with the frequency that can be programmed using external resistor and capacitor, typically 40~50 KHz. The internal circuitry of the device allows it to be driven also by external logic signal. The output drivers are designed to drive external n-channel power MOSFET and IGBT. The internal logic assures a dead time typically being 1.25μs to avoid cross conduction of the power devices. Compared with other ICs, the SPIC integrates a bootstrap diode in it by using the patent of the Professor Xingbi Chen. This can bring us more stability and less cost. Besides, an under-voltage lockout circuit is provided in the device.