an innovation by nucon.de

The sensorless temperature method can be easily integrated into concepts already using a PWM dimming. The extra component costs assuming there is already a micro controller for the dimming inside a design is very low. The software resources for the measurements and calculations are also very low so it can be even performed by 8 bit cheapest  controllers. The high precesion and resolution is coming from averaged repeating measurments and the fixed frequency of the controller. 10-12 bit ADC  is good enough.

Besides automotive headlights there should be a wide range of products for a possible integration. Especially when there is a critical product size and varying operating conditions are likely leading to over heating conditions of the LED. In this case an extra temperature sensor can be saved and or the system response and protection can be further increased to grant the maximum life time of the LEDs.

Examples of small portable products are smartphones, cameras, bike lights, torch lights, video lights, etc. in which because of weight and size a big cooling block can not been integrated. It is to be expected that at longer times of operation a hot spot will be present. Almost everywhere thermal protection makes sense. The cost reduction of service replacements and warranties will be significant.

Detailed pictures of the inside of new Samsung S6 smartphone are showing a very small carrier board of the camera flash LED. Our solution can grant always light under continuous operation, especially when the light is used for the torch app or taking a movie.

LEDs of much higher wattage like uplights may need to have an active cooling like computer processors cooling with a blower. There is the same problem and the same reliability achieved because the processor uses also a temperature integrated sensor, without en external sensor mounted on the cooling block.

There are several failure modes possible: An external sensor does not show the right temperature of the LED, because of a missing thermal interface material placed in between the LED and the cooling block, an aged thermal grease, a non contacted sensor or even a bad calculated thermal system leading to wrong assumptions.

At very high power loads the LED must be always hotter than an external sensor since there will be a gradient in between two different positions by nature. There is a certain danger even at the engineers design stage, that this difference is underestimated like what you don't know or can't measure right does not exist. It may even comes to some new product developments because a thermal sensor-less protection is a precondition. When considering end users replacing servicing LED chips without glue or any soldering for lights to be in use permanently on, like in tunnels. It can be the base for a long time operation.

Our solution is always fast, precise, reliable and always active is the LED is in use.

 

You can do  real LED replacements in existing designs driving the LED as hot as the assembly is capable for cooling:

  

The temperature sensing over just a long supply harness leads to new design ideas like smallest high power clipable helmet lights and so on.