Method for detecting LED driving circuit

Abstract

A method for detecting an LED driving circuit. A processing unit generates a fixed frequency for respectively driving each string of field effect transistors, then a respective current value is generated, a voltage value converted by the current value of the each string is obtained through a current detection resistor, the voltage values are compared with each other, if the voltage values are different, the processing unit can automatically generate different frequencies and different ripple currents, then series connected branch currents are compared with each other respectively, so as to obtain a current mostly near the optimum, the driving frequency and the ripple current at the moment enable the LED to emit light uniformly, i.e., for the method in a multi-parallel multi-series LED light, the LEDs connected in series on a parallel connection circuit cannot cause short circuit due to damage of one LED, or when forward voltages of the LEDs are greatly different, the current rises extremely, the situation that the series of LEDs are excessively bright and the normal LEDs connected in series on the other parallel connection circuit are not bright occurs, therefore the service life of an LED light fixture can be prolonged.

Description

technical field [0001] The invention relates to a detection method, in particular to a detection method for a light-emitting diode driving circuit. Background technique [0002] At present, the LED driver on the market is driven by a constant current, and the LED lamps used are in parallel LED arrays, which is prone to potential differences, because when the LEDs are paralleled together, the mismatch of current flowing in different branches will cause Therefore, before assembling the LED lamps, the voltage classification (binning) of each light-emitting diode (LED) must be done first. The LEDs of the same voltage are connected in series and then in parallel before being combined, so as to create a good environment for them to work normally. Conditions, but when one LED is damaged and causes a short circuit, which destroys the entire normal working environment, all the driving current will flow to the rest of the LEDs, resulting in overheating, causing the entire LED to be da...

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Problems solved by technology

[0002] At present, the LED driver on the market is driven by a constant current, and the LED lamps used are in parallel LED arrays, which is prone to potential differences, because when the LEDs are paralleled together, the mismatch of current flowing in different branches will cause Therefore, before assembling the LED lamps, the voltage classification (binning) of each light-emitting diode (LED) must be done first. The LEDs of the same voltage are connected in series and then in parallel before being combined, so as to create a good environment for them to work normally. Conditions, but when one LED is damaged and causes a short circuit, which destroys the entire normal working environment, all the driving current will flow to the rest of the LEDs, resulting in overheating, causing the entire LED to be damaged one by one like a defeated army. Because the luminous level or brightness of the LED is usually proportional to the size of the forward current, the current through the LED should not exceed the rated current specified by the device, otherwise it will cause permanent damage

[0003] At present, the LED driver (LED driver) on the market is designed with a stable current in order to improve the life of the LED. However, if the LED voltage binning is not done well, the error will be large, or one or more strings of one LED or more LED damage and short circuit will cause the temperature to rise, and the life of the LED will be reduced early

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