How to dim LED lighting

There are five LED lighting control methods on the market:

Front edge phase cut (FPC), thyristor dimming

2. Rear edge phase-cut (RPC) MOS tube dimming

3. 1-10V dimming

4. DALI (Digital Addressable Lighting Interface)

5. DMX512 (or DMX) dimming

Front edge phase-cut control dimming

The leading edge dimming is to use a thyristor circuit, starting from the AC phase 0, the input voltage is chopped, and the voltage input is only available when the thyristor is turned on. The principle is to adjust the conduction angle of each half wave of the alternating current to change the sinusoidal waveform, thereby changing the effective value of the alternating current, thereby achieving the purpose of dimming.

The leading edge dimmer has the advantages of high adjustment precision, high efficiency, small size, light weight and easy remote control. It is dominant in the market, and most manufacturers' products are this type of dimmer. Leading edge phase control dimmers typically use thyristors as switching devices, so they are also known as thyristor dimmers.

The advantages of using an FPC dimmer on an LED illuminator are: low dimming cost, compatibility with existing lines, and no dimming to control dimming after phase rewiring. The disadvantage is that FPC dimming performance is poor, often resulting in a reduced dimming range, and will result in the minimum required load exceeding the rated power of a single or a small number of LED lights. Because of the properties of the thyristor half-control switch, only the function of turning on the current can not completely turn off the current, even if it is adjusted to the lowest, there is still a weak current, and the characteristic of the LED micro-current illuminating makes the thyristor dimming exist in a large amount. After the shutdown, the LED still has a weak luminescence phenomenon, which has become a problem in the current promotion of the wiring-free LED dimming method. El The leading edge phase-cut LED dimming driver developed by inker Yilian has solved this problem very well. Through the “C-TURN OFF” technology of the drive circuit, it is easy to avoid the problems of “continuous” and “stroboscopic bad light”. Match El Inker's front-phase phase-cut LED dimming driver can be perfectly matched with other thyristor dimming systems, saving users wire and wiring man-hours, solving thyristor LED dimming matching and non-turning off. Chaotic pattern.

Back edge phase-cut control dimming

The trailing edge phase-cut control dimmer is fabricated using field effect transistor (FET) or insulated gate bipolar transistor (IGBT) devices. The trailing edge phase-cut dimmer generally uses a MOSFET as a switching device, so it is also called a MOSFET dimmer, commonly known as a "MOS tube." The MOSFET is a fully controlled switch that can be controlled either on or off, so there is no thyristor dimmer that cannot be completely turned off. Another MOSFET dimming circuit is more suitable for capacitive load dimming than thyristor, but because of the high cost and relatively complicated dimming circuit, it is not easy to be stable, so the MOS tube dimming method has not developed, thyristor tuning Optical devices still occupy the vast majority of the dimming system market.

Compared to leading-edge phase-cut dimmers, trailing-edge phase-cut dimmers are used in LED lighting equipment, and because there is no minimum load requirement, better performance can be achieved in a single lighting device or very small loads, however, Since MOS tubes are rarely used in dimming systems, they are generally only made into knob-type single-lamp dimmer switches. This low-power rear-cut phase dimmer is not suitable for engineering applications. Many lighting manufacturers use this dimmer to do dimming tests on their own dimming drivers and lamps. Then, the dimming products of their own are pushed to the engineering market, which leads to the situation that the phase-cut dimming drive is modulated by the thyristor dimming system. This mismatch in dimming mode causes dimming to flicker, which can quickly damage the power supply or dimmer.