How to solve the heating problem for led strip light?

LED strip light is widely used and the price is beautiful.But led strip light also has its own shortcomings.The main problem is heating.Now let’s analyze the cause of the heating.

1. Circuit design issues: the most commonly used specifications for LED strip light are currently two voltages of 12V and 24V. 12V is a 3-string multi-parallel structure, and 24V is a 6-string multi-parallel structure. Since the led strip light is to be connected and used, the length of each led strip light can be connected has a lot to do with the width of the circuit and the thickness of the copper foil when designing. Because the current intensity per unit area is related to the cross-sectional area of the circuit, if this is not considered when wiring, then when the connection length exceeds the current that the circuit can withstand, the led strip light will be caused heating by overcurrent. Heating, while damaging the circuit board, also reduces the service life of the LED.

2. Production process problem: since the LED strip light is a series-parallel structure, when a short circuit occurs in a certain group of loops, it will cause the voltage of other LEDs in the same group to increase, and the brightness of the LED will increase, and the corresponding heat will also rise. The most obvious is that in the 5050 light strip, when any chip loop of the 5050 light strip is short-circuited, the current of the short-circuited lamp bead will double, that is, 20mA becomes 40mA, and the brightness of the lamp bead will become very bright, but at the same time the heat will also increase sharply, and in serious cases, it will burn the circuit board in a few minutes. However, because this problem is relatively obscure, it is generally not noticed because a short circuit does not affect the normal light emission of the light strip. If the staff in charge of the test only pays attention to whether the LED is shining, and does not check for abnormal brightness, or does not do visual inspection, if only electrical testing is done, this problem is often overlooked, which is why many LED strip light manufacturers always encounter customer complaints that the product is very hot but cannot find the reason.

 Solution:

1. Circuit design:

The loop should be as wide as possible, the spacing between the lines should be 0.5mm, and the rest of the space should be full. The thickness of the copper foil is as thick as possible without violating the customer's requirements for the total thickness of the circuit board, and the general thickness is 1~1.5OZ;

2. production process:

A. When printing solder paste, try not to allow solder connection between the pads to avoid solder short circuits caused by poor printing;

B. Avoid short circuits when patching;

C. Check the placement of the patch before reflow;

D. Perform visual inspection after reflow to make sure that the light strip is not short-circuited, and then re-check the electrical test. During the re-check, pay attention to whether the LED is abnormally bright or abnormally dark.

After analyse the reason of heating problem for led strip, and give a solution, LED strip light can be done to avoid the problem above.