LED light tube compatible with electronic ballast

Abstract

The invention discloses an LED light tube compatible with electronic ballast. The LED light tube comprises a waveform conversion circuit and at least an LED lamp string. The waveform conversion circuit is directly connected to the electronic ballast and uses a rectifier diode have recovery time of less than 2.5 us. The at least an LED lamp string utilizes a plurality of LED elements having recovery time of less than 2.5 us. When the power switch of a lamp base is switched on, the electronic ballast takes the waveform conversion circuit and the at least an LED lamp string as low-impedance loads to not output high starting voltage. The waveform conversion circuit and the at least an LED lamp string use components to match a 20KHz to 40KHz high-frequency AC power supply, so that the high-frequency AC power supply is prevented from being burnt.

Description

technical field [0001] The invention relates to an LED lamp tube, especially an LED lamp tube compatible with an electronic ballast. Background technique [0002] Generally, the lamp holder is used to light up traditional fluorescent tubes, such as T5 or T8 lamps. The lamp holder will be equipped with a starter to match with a traditional ballast or directly use an electronic ballast without a starter. Because the traditional lamp must be started at high voltage to start smoothly, both the traditional ballast and the electronic ballast will start the output voltage as high as 1000V when the AC power is turned on. When plugging in the socket, the wires between the ballast and the lamp socket must be cut off, and then connected to the AC power wire to start normally; large and burnt, such as Figure 5 As shown, taking a linear LED lamp tube as an example, it includes a bridge circuit 50 and an LED unit. The LED unit 60 includes a light string 61, a driving switch 621 and a dr...

AI Technical Summary

Problems solved by technology

[0003] Furthermore, there are currently many lamp holders that use electronic ballasts to provide traditional lamps with a high-frequency AC power supply to improve the abnormal sound and flicker of the starter and the defects of low service life of traditional lamps; however, due to electronic ballasts The high-frequency AC power output by the converter causes the LED lamps using bridge rectifiers to be burned; the main reason is that the low-speed rectifier diodes used in general bridge rectifiers are only suitable for low-frequency AC power such as 60Hz, but for high-frequency power up to at least 20KHz AC power supply, because of its long voltage recovery time, it will still be burned when used in high-frequency AC power supply

In addition, when the electronic ballast first starts the traditional lamp with high-voltage and high-frequency AC power, because the lamp turns to low impedance, the current output by the electronic ballast is a constant current to drive the low-impedance However, because the driving circuit of the LED lamp is generally designed according to the AC mains power supply, the AC mains power supply has a constant voltage of 110V or 220V, so it cannot convert the constant current AC power output by the electronic ballast to LED lamp drive power supply

[0004] Therefore, at present, no matter whether the LED tube lamp is an exchangeable LED tube type or a linear LED tube type, unless a power supply protection circuit or a conversion circuit is added to the characteristics of the AC power output of the electronic ballast, it cannot be directly inserted into the lamp socket for use; and this It is also one of the reasons why LED light tubes cannot be popularized at present, and it is necessary to further improve them.

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