AC driven LEDs

AC driven LEDs are rare but popular in certain applications. Designers focus on LEDs because of their advantages like direct, brilliant light, strong color saturation, slim measurements, dynamic lighting scenes and in total all the design possibilities that are thinkable. The only restrictions are made by the heat that needs to be dissipated by surface, natural or forced ventilation and the driver’s measurements. The driver is mostly not slim at all. That is why AC driven LEDs can be a smart consideration.

Conventional LEDs, Modules and Light Engines are driven by DC (direct current) power supplies. The LED characteristics are highly dependent on these components as they control the inrush current, convert the alternate current down to DC voltage and stabilize the current the LEDs are driven with. The efficiency of the system is dependent on the driver too as the power factor is one part in the total sum. Most conventional DC power supplies support LED systems with power factors (PFC) of 0.9 and higher.

The lifetime of LED lighting systems is defined by electronic devises. The LED can last up to 100,000h but if the driver needs a replacement after 50,000h the system is only half worth the maintenance. Without any driver at all the problem is solved completely. Power supplies need space, no matter how small, the driver is mostly bigger than the LED modules and electronic component’s wiring needs space too. Without this item there are not restrictions in design any more than heat dissipation. Designers can release their full creativity.

AC driven LEDs are of advantage concerning design and lifetime options. The more complex the circuit, the higher the possibility of system failure and electrical noise. On the other side, the efficiency of AC driven LED modules is not that high like DC driven ones. The performance achieves 110 lm/W these days which is good compared to other light sources but behind DC driven LEDs with up to 140 lm/W and more. AC driven LEDs are a thinkable substitute in applications like bulb lights, downlights, ceiling lights and industrial lighting systems.