Electronic device, constant current unit and method for stabilizing current

Abstract

The invention relates to an electronic device which comprises a rectification unit, a load and a constant current unit, wherein the load is electrically connected with the rectification unit and used for receiving a rectification signal output by the rectification unit for action; the constant current unit comprises a first constant current circuit, a second constant current circuit and a first branch circuit, wherein the first constant current circuit and the second constant current circuit are connected in series with the load, the first branch circuit is connected in parallel with the first constant current circuit, the first constant current circuit can regulate the impedance per se to maintain the current passing through the load to be a first current value, the voltage drop of the first constant current circuit is constantly lower than a first voltage drop upper limit value, the second constant current circuit can regulate the impedance per se to maintain the current passing through the load to be a second current value, the second current value is higher than the first current value; when the voltage drop of the first branch circuit is more than a first operating voltage value, the first branch circuit enables the current to pass through, and the first operating voltage value is not more than the first voltage drop upper limit value. The invention aims at ensuring than an LED is not easy to generate thermal runaway by using AC as a power supply and the current capable of stably passing through the LED.

Description

technical field [0001] The invention relates to a device capable of emitting light, in particular to an electronic device capable of emitting light and using alternating current as a power source. Background technique [0002] The basic characteristics of traditional light emitting diodes (Light Emitting Diode, hereinafter referred to as LED) are unidirectional direct current (referred to as DC) drive, which is quite different from the type of alternating current (referred to as AC) used in general indoor lighting equipment. . [0003] In order for LEDs to operate normally under AC power, conversion equipment such as transformers and rectifiers must be used to convert AC power to DC for driving. However, whether it is connected to a converter or embedded in the product, the product will increase Size, weight and cost will also cause additional power consumption. In addition, an LED that can only withstand a voltage of 2-4 volts is far from the reality of hundreds of volts ...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to overcome the defects of existing diodes and provide an electronic device with a new structure. The technical problem to be solved is that AC can be used as a power source and the current passing through the LED can be stabilized so that the LED is not easy to generate thermal run-off phenomenon. , very suitable for practical

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