White LED light beads always fail or die is what causes

White LED beads are voltage sensitive devices, packaging companies have different working currents and working voltages under different packaging brackets, take the typical package as an example (2835); in actual operation is the current of 60mA as the upper limit, but often due to various reasons in use and cause the current to increase, if no protective measures are taken, this increase in current over a certain time and magnitude after LED lamp beads will be damaged.

The main reasons for the damage of LED lamp beads are:

① The sudden rise of the supply voltage, beyond the voltage stabilization range of the lamp power supply, resulting in the rise of the voltage at the output end, and thus the lamp beads burned.

②The short circuit of a component or printed lines or other wires in the line and the formation of a local short circuit in the power supply path of LED beads, so that the voltage in this place is increased, thus burning the beads or other components of the circuit board.

③ A LED bead is damaged because of its own quality and thus forms a short circuit, and its original voltage drop is transferred to other LED beads.

④The temperature inside the lamp is too high, so that the current of the LED beads increases and the beads are burned.

⑤ The lamp bead board is not waterproof, the surface condensation formed condensation water, causing the line or lamp bead burned.

So, what should we do to avoid the above problems and carry out the protection of the LED lamp bead circuit?

A, in order to avoid the first problem occurred we should take measures.

The power supply of the lamp is generally AC 180 ~ 240V AC power through rectification, filtering, voltage stabilization to ensure the output of low-voltage 12 ~ 72V DC power for LED lamp beads light use.

1, improve the performance of the power supply itself, to achieve wide voltage input; generally can ensure that 130V ~ 265V input voltage, the output voltage changes within 3% range.

2, increase the linear constant current circuit at the output side of the voltage regulator, so that the lamp bead current does not change with the change of input voltage.

Second, in order to avoid the occurrence of the second and third problems we should take measures

1, the choice of lamp beads as far as possible when using qualified components to ensure the stability of the light source board.

2, light source internal light source board as little as possible to install circuit components, it is best to install only lamp beads and constant current IC.

Third, in order to avoid the occurrence of the fourth and fifth problem we should take measures

1, in order to ensure that the internal temperature of the lamp is not high, increase the heat dissipation area of the lamp body, to ensure that the heat dissipation area of 50 square centimeters per W.

2, the lamp bead board must do with epoxy resin to do waterproof treatment, to avoid the surface of the lamp bead board because of the climate and condensation.