Why Digital Control Technology prevails in LED dimming function for LED street lamps?

Why Digital Control Technology prevails in LED dimming function for LED street lamps?

  Although LED street lamps are best-selling across the industry, it has some limits particularly in dimming. Indeed, general driver is not able to provide satisfactory dimming performance, energy efficacy and reliability within appropriate prices. In some applications including family, restaurant and some similar places, smooth and glare-free dimming function is needed.

  Triac-integrated dimmer is designed to drive the resistor load. This also can be called Frontal dimmer, which generate via postponing triac switch.

  When giving a signal for triac dimmer, supposing that current in normal requirement, then double switch begins to run and keep it run in the left normal period. However, two factors can restrict light dimming range even for the incandescent lights. Dimming circuit usually covers EMI filter, which introduce the noise into inductor and capacitor. If it is a low-quality inductor, the noise can be able to enable current below requirement, which can produce the glare.

  Fig 2. Minimum load currents for five triac-integrated dimmer minimum load currents are compared. The peak showed that LED driver needs minimum current to ensure correct operation.

  A common solution to above problem is to discharge circuit — Keep enough circuit on triac in lower dimming level. Two defects exists to use passive release. The first one is efficacy lose and another one is about heat dissipation impacts on life span. Heat management is crucial to LED street lamps. LED can run range from 25,000 to 50,000 hours. However, some components are more sensitive to operational temperature. The temperature rises up for 10°C, while the life will lower by 50% for capacitor.

  A satisfactory solution is to recycle the leak current instead of heat. Previously speaking, it is not easy to accomplish. While, digital technology can give a big help through smart control heat needed.

  Additionally, IC digital circuit is in charge of relative voltage and current to achieve dimming as needed. IC also integrates smart function to freely adjust impedance as the dimmer character, which can help better adjustment to improve efficacy.

  Customers invariably expect better lighting effect, which need whole industry constantly to upgrade current technology. New technology must be introduced at competitive price; meanwhile, it must improve energy efficacy and reliability. In a word, digital technology in LED street lamps provides a better solution to satisfy the customers’ expectation.