LED drive circuit and drive device

Abstract

The invention discloses an LED drive circuit and a drive device. The LED drive circuit comprises an LED light-emitting module, a silicon controlled rectifier regulator used for regulating the brightness of the LED light-emitting module, a first constant current source module, a second constant current source module, a third constant current source module, an energy storage module and a protectionmodule, wherein the first constant current source module is used for providing drive current for the LED light-emitting module; the second constant current source module is used for providing discharge current for the silicon controlled rectifier adjusting module and maintaining current for maintaining conduction of the silicon controlled rectifier adjusting module when the on-line voltage is smaller than the conduction voltage of the LED light emitting module; the energy storage module is used for supplying power to the LED light-emitting module when the on-line voltage is smaller than the conduction voltage of the LED light-emitting module; the third constant current source module is used for adjusting the output current of the LED light-emitting module; according to the LED drive circuit, the anti-surge capacity can be effectively improved, and the working safety of the LED drive circuit is guaranteed.

Description

technical field [0001] The invention relates to the technical field of LEDs, in particular to an LED driving circuit and a driving device. Background technique [0002] Such as figure 1 As shown, in the existing LED driver circuit using thyristor dimming, when the phase of the thyristor dimmer is cut, a discharge current is required, otherwise it will cause abnormal operation. However, when the online voltage of the LED lamp is lower than the lighting voltage of the LED lamp, no current flows through the LED lamp. Therefore, an additional discharge circuit is added to the LED drive circuit compatible with the thyristor dimmer. However, since the discharge current does not flow through the light string, but only flows through the resistor Rb and the first constant current source SC1, when a high voltage surge occurs in the power supply network, the surge high voltage is borne by the resistor Rb and the first constant current source SC1 , it is easy to cause damage to the re...

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Problems solved by technology

[0002] like figure 1 As shown, in the existing LED drive circuit using thyristor dimming, when the phase of the thyristor dimmer is cut, a discharge current is required, otherwise it will cause abnormal operation

And when the online voltage of the LED lamp is lower than the lighting voltage of the LED lamp, the LED lamp has no current flow, so the LED drive circuit compatible with the thyristor dimmer will add an additional discharge circuit

However, since the discharge current does not flow through the light string, but only flows through the resistor Rb and the first constant current source SC1, when a high voltage surge occurs in the power supply network, the surge high voltage is borne by the resistor Rb and the first constant current source SC1 , it is easy to cause damage to the resistor Rb and the first constant current source SC1, resulting in abnormal operation of the LED drive circuit

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