LED (Light Emitting Diode) light tube driving circuit suitable for backup power supply fixture lamp

Abstract

The invention discloses an LED (Light Emitting Diode) lamp tube driving circuit suitable for a backup power supply fixture lamp. The LED lamp tube driving circuit comprises a high-frequency rectifying and filtering module, a working mode detection module, a dimming constant-current driving module and an LED light source module, wherein the high-frequency rectifying and filtering module, the working mode detection module, the dimming constant-current driving module and the LED light source module are mutually connected. The high-frequency rectifying and filtering module includes a protection unit, a rectifier bridge unit and a filtering unit and is used for rectifying and filtering a high-frequency pulse power supply after inversion by a reserve power supply. The filtering unit includes electrolysis conpacitors CE1 and CE2, a difference module inductor Ld2, a common mode inductor T2, capacitors C3A and C3 and a resistor R11. Compared with the prior art, a mains supply rectifying and filtering circuit in the traditional LED fluorescent lamp tube circuit is changed into the high-frequency rectifying and filtering circuit, non-dimming constant-current driving is changed into the dimming constant-current driving, and a working mode detection circuit is added so as to ensure that the LED light source module can normally work in an emergency illumination mode when the backup power supply supplies power to the fixture lamp or a nameplate and the like, thus, the service life of the LED light source module, the fixture lamp or the nameplate can be prolonged; and the LED lamp tube driving circuit is energy-saving and environment-friendly.

Description

Technical field [0001] The invention relates to the technical field of back-up power supply bracket lamp circuits, in particular to an LED lamp tube drive circuit suitable for back-up power supply bracket lamps. Background technique [0002] At present, in order to ensure personal safety, bracket lights or signs are generally installed in corridors, emergency passages, and safe fire passages of commercial buildings. The bracket lamp or the sign board belongs to an emergency lighting product with a backup power supply mode. [0003] The bracket lamp or signboard generally works in the state of a permanent light, and is in two states of normal lighting and emergency lighting. When the mains power is used to supply power to the bracket lamp or the sign, it is in the normal lighting mode; when the backup power supply is used to power the bracket lamp or the sign, it is in the emergency lighting mode. Such as figure 1 As shown, the circuit of the existing bracket lamp or sign plate in...

AI Technical Summary

Problems solved by technology

However, since the mains rectification and filtering circuit is only designed with low frequency (less than 1KHz) in mind, the loss of high frequency power rectification and filtering is serious, and it does not have dimming function and power supply voltage detection function.

When the LED lamp tube is used for the backup power bracket lamp, the mains power supply can be normally lit, but after the mains power failure, due to the small power of the backup power supply, it will go out or flicker, and cannot work normally

Images