People's demands for energy continuously increase with the progress in various technological fields. To avoid shortage or even depletion of energy resources, endeavors have been made to discover new energy sources. On the other hand, effective means have also been developed to minimize the power consumption of existing electric and electronic devices.
Lighting fixtures account for a very large part in all kinds of power-consuming devices. Presently, the bases for general lamps are mainly divided into two types, namely, conventional and electronic lamp bases. The conventional and the electronic lamp base all are equipped with a starter, but have a conventional and an electronic ballast, respectively. The conventional ballast and the electronic ballast are different in their wiring configuration, fundamental characteristics, use manners and power consumption. The biggest difference between the conventional and the electronic ballast is that the conventional ballast uses a low frequency of 60 Hz, while the electronic ballast uses a high frequency ranged between 30,000 and 50,000 Hz.
Since the lighting fixtures account for a very large part in the power-consuming devices, improvements of the power consumption efficiency of lighting fixtures and development of creative use manners thereof have become new and important issues. Among others, the use of LEDs to replace the conventional illumination light sources has become a frequently adopted technical means for improvement of various kinds of lighting fixtures. In recent years, the LED-related technique develops quickly to largely widen the applications of LEDs. There are more and more daily necessaries with LEDs. The LED illuminates light using high current with low voltage, and has the advantages of long service life, low power consumption and low heat production. With these advantages, LEDs are environmentally friendly and attract many manufacturers to the research and development of LED tube lights.
Driving circuits for LED tube lights are generally divided into three types according to their technical features. In the first type of driving circuit for LED tube light, two circuit boards are included, one of which is a power driving circuit board while the other one is an LED circuit board. The power driving circuit board and the LED circuit board are electrically connected to each other via conductors or connection terminals and all are mounted in the tube light, so that power can be effectively supplied from the power driving circuit board to the LED circuit board to produce light sources. In the second type of driving circuit for LED tube light, three circuit boards are included in the LED tube light. Two of the circuit boards are power driving circuit boards while the third one is an LED circuit board. The two power driving circuit boards are separately arranged at two opposite ends of the tube light, and the LED circuit board is arranged in the tube light at a middle section thereof and electrically connected via conductors or connection terminals to the power driving circuit boards located at two opposite ends of the tube light, such that power can be effectively supplied from the power driving circuit boards to the LED circuit board to produce light sources. In the third type of driving circuit for LED tube light, only one LED circuit board is included in the LED tube light. The LED circuit board is connected via conductors to two pinned bases mounted to two opposite ends of the tube light, and a power driving circuit is arranged outside the tube light or in a corresponding lamp base.
In either one of the above-mentioned three types of driving circuits for LED tube light, complicated wiring is required to achieve electrical connection between the LED circuit board and the power driving circuit boards or the externally arranged power driving circuit. Since the tube light has only very limited internal space, complicated working procedures are needed to mount the LED circuit board and the somewhat bulky power driving circuit boards in the small internal space of the LED tube light, which inevitably largely increases the manufacturing and material costs of the LED tube light.