Among the issues of LED power supply is one of the latest challenges still yet to be fully solved. Dimming LEDs is theoretically easy, because analogue dimming, that is the adjustment of current, has always been an option. However, this method only works safely when used with one LED bulb. Systems of LEDs need a more sophisticated method of dimming. The 2 basic forms of dimming are definitely the PWM or Pulse-Width-Modulation as well as the analogue dimming, both of which are switched-mode regulators. Both of these types are similar within the sense that they both control the time-averaged current through the diode.
Analogue dimming is definitely a simple way of dimming, it is the adjustment of cycle-by-cycle of the LED current regulated using a potentiometer. The current is adjusted to the LED increasing and decreasing its intensity.
The downside of analogue dimming is it only works safe as long as we dim a single bulb. Systems of LED lights demand a more refined technique. The difficulty of dimming a method of Leds is that there are various kinds of LEDs, requiring different methods for dimming. If there is a method of lights we wish to dim, the different LEDs may react diversely to the same amount of current, and as the current is reduced some LEDs can change off later or sooner than others. Also, analogue dimming largely changes the color of the light, similarly to when it is combined with incandescent lights.
By far the most frequently used technique of 12v dc power supply led is Pulse-Width Modulation, that is basically the cutting of the phase at a certain frequency. PWM switches the devices between fully on and fully off in a frequency that should not be told through the human eye, therefore LED bulbs always run on the forward current recommended. The frequency of switching determines the brightness of light, and so the longer the lights are “on” the brighter the light will be. Here is the same technique used in incandescent light dimmers as well, except that incandescent lights react to current slower, and for that reason need a different frequency.
2 kinds of Pulse-With Modulation signals are employed often with dimming light: the key-edge as well as the trailing edge techniques. These two will vary means of cutting the phase, and bring about separate dimming technologies. The most frequently used dimmers of LEDs use solely the leading-edge technology.
Dimmers marked as R or RL are suitable for most dimmable LEDs, because they work together with the key edge technology and do not include electronic transformers. TRIAC drivers, or devices governed from the DMX and digital addressable lighting interface (DALI) protocols and, down the road, can include wireless (RF) as a control option, that is dimmers that turn or slide having a knob, all work together with dimmable LEDs. Alas leading edge technologies controlled with a touch or push button, are nzyjty powered by an electric powered transformer, excluding many dimmable LEDs.
One other kind of phase-cutting technique is trailing edge technique, usually utilized in MOSFET or possibly is not suitable for almost all dimmable LEDs. One of the latest inventions appearing on the industry is the RAIS lamp technology. RAIS lamps provide a higher level of functionality and seem to do business with all kinds of dimmers available on the market. However RAIS technology continues to be new, along with its long-term influence on LEDs have not been fully tested. Should they end up being trustworthy their application both domestically and commercially, can grow to be much safer and easier than previous dimmable LED lights’.
Within the ever-evolving technologies of Leds, led power 12v continue to be to be created to further compatibility and performance. As there is no general rule for the purpose dimmer your LED might be ideal for, make sure the technical details with the distributor. Implementation of Leds with non-compatible dimmers might ruin the LEDs, and they are generally, currently, not the least expensive solution of lighting.