LCD Display Inverter

Display Inverter / VGA Board / LCD Controller

Based on a LED control circuit design suitable for SSL products

This method is applicable to SSL products with LED-based control circuits and heat sinks, and is applicable to luminaire forms (including light source units) as well as integrated LED lamps, i.e. these devices require only AC or DC power to operate; not suitable for external operation SSL products with circuits or external heat sinks, such as LED chips, LED packages and LED modules, are also not suitable for installations designed for SSL products without a light source.

1.Scope of application

This method is applicable to SSL products with LED-based control circuits and heat sinks, and is applicable to luminaire forms (including light source units) as well as integrated LED lamps, i.e. these devices require only AC or DC power to operate; not suitable for external operation SSL products with circuits or external heat sinks, such as LED chips, LED packages and LED modules, are also not suitable for installations designed for SSL products without a light source.
  

 

2.Measurement parameters

Light parameters: total luminous flux, luminous efficiency, light intensity distribution, chromaticity coordinates, correlated color temperature and color rendering index; electrical parameters: input AC (or DC) voltage, input AC (or DC) current, input power (DC or AC) , input voltage frequency and power factor.

3. Environmental conditions:

1) Air temperature: 25°C ± 1°C;

2) Thermal environment: The installation method is the main path for heat dissipation of the device and may greatly affect the measurement results. The SSL product under test shall be mounted on a measuring instrument (eg integrating sphere) so as to be slightly cooled by the heat conduction cooling effect of the supporting facility.

3) Air flow: The air flow on the surface of the tested SSL product may greatly change the power value and photometric value, and the air flow around the tested SSL product should keep the normal convection gas unaffected. In order to ensure that the air temperature meets the conditions, some domestic equipment manufacturers adopt the method of inputting cold air into the integrating sphere, which is obviously not desirable. As for how to ensure the air temperature during the test as much as possible, there are actually some tips in the test process. In the blog post of the issue, it is mentioned one after another. In addition, some distributed photometers use the lamp-turning structure, which obviously violates this principle.

4.working direction

The light-emitting process of the LED is not affected by the orientation, but the orientation of the SSL product will change the thermal state generated by the LED on the product, so the light output may also be affected by the orientation of the SSL product. The SSL product under test should be evaluated in the final use environment of the product recommended by the manufacturer, that is to say, the test environment of the SSL product should be as consistent as possible with the final use environment. When installing, ensure that it emits light upwards; when testing suspended lamps, it can be measured at 4π by fixing the rod from top to bottom in the integrating sphere at the center of the ball; and for stage projection lamps, because they have a certain projection angle when they are finally used, When measuring, it can be installed on the ball wall and ensure a certain projection angle. From this point of view, only the rotating integrating sphere in the integrating sphere system strictly meets this standard.

5.Device Selection

The total luminous flux of SSL products should be measured using an integrating sphere system or a distributed photometer. The choice depends on whether other measurements (color, intensity distribution) need to be measured, as well as SSL product size and other requirements.