Latest LED drivers offer high efficiency and lower power consumption

The constant pressure to reduce chip sizes and increase lumens per watt has forced manufacturers to come up with modified drivers equipped with the latest technologies

By Kartiki Negi

Wednesday, March 19, 2014: A successful ballast design has to be a delicate balance of a number of countervailing factors—ease of use against design complexity and cost; voltage and current control against design complexity and board space; and functionality against low power consumption.

LED ballasts or LED drivers provide LEDs with a constant source of current. A high current LED ballast forms an important part of an LED bulb.

What’s new in the market?

EOS Power India has recently launched a 45 W LED ballast capable of driving an LED string at a constant current of 1.5 Amperes. Launched this January, it is available in a metal as well as plastic casing. This range caters to the demand for lighting in offices, operation theatres, cinema halls, shopping malls, residential spaces, etc.

“Our 45 W LED ballast’s wide input range makes it very useful in the rural areas of India where the AC line falls well below 150V AC. Its metal enclosure and high efficiency makes it rugged enough to work at high temperatures of up to 50 C. It automatically shuts down when put on ‘no load mode,’ that is, when LEDs are not connected or are open. This reduces power drawn from AC mains. Our product is designed to meet stringent international safety standards like UL, CSA, TUV, NEMKO, etc,” says Sanjay Sawant, design manager, EOS Power India.

Advanced Powertech has introduced phase cut drivers (triac dimmers) and DALI (digital addressable lighting interface) compatible drivers. “Our equipment is the most suitable for indoor mood lighting and individual light addressing systems as well as for power saving using DALI drivers. The unique quality of our products is that they enable users to programme individual LED lights,” says Ajay Nahata, managing director, Advanced Powertech.

In January, Nippon India launched the new Meanwell DAP-4, DALI-to-PWM converter for LED drivers. This new product makes the DALI control possible on LED lighting fixtures. “DAP-04 is equipped with both DALI dimming and push-dim functions. When connecting to the external DALI controller, it can convert the DALI signal transmitted from the controller to a PWM signal, and then the PWM signal can control the lighting fixtures through the ‘3-in-1 dimming’ interface,” says Anil Joshi, managing director, Nippon India.

Moxie Devices has recently introduced the HP series of non-dimmable LED drivers ranging from 12 W to 18 W. The drivers have protection for short circuits, input over voltage, output open circuit and over temperature. “Our series is used in a wide array of indoor LED decorative lighting, architectural lighting, office lighting, downlighters and LED electrical displays,” says P K Jain, director, Moxie Devices.

Technological advancements

The constant pressure to reduce chip sizes and increase lumens per watt has forced manufacturers to come up with modified drivers equipped with the latest technologies, which could further enhance the efficiency of LED lighting and make it more cost effective. They are now coming up with automated features and water proofing/moisture protection and a lot more.

EOS Power’s recently launched 45 W LED comes with the active power factor correction at the input stage that improves the power factor to > 0.95. It uses single stage PFC, which reduces the component count and thus reduces the cost. Besides, reduced ripple at the output gives the intended luminous flux.

The HP series of non-dimmable LED drivers is highly efficient and has a long life. It offers a wide input voltage range and thus results in lower power consumption. It is a constant current LED driver with universal input voltage, power factor correction and efficiency of > 81 per cent.

Nippon India’s Meanwell DAP-4 features 90~305V AC input and power consumption of <0.5W. DAP-4 can be cooled by free air convection from -30°C to +60°C ambient temperature that is required for operating in a closed system. Enclosed by a UL 94V-0 rated plastic case and Class II double isolation design (without FG), these units can effectively prevent users from getting an electrical shock. The I/O terminals of DAP-4 are designed with a screwless clamp style terminal block, which allows users a more convenient wiring installation.

“Each output channel of DAP-4 can connect with the dimming control input of LED PSU for up to 20 units, which means the four output channels on the converter can connect with a total of up to 80 units. Each channel has an independent DALI address and can be controlled separately, which fulfills the demands of intelligent lighting control systems that require energy-saving, high efficiency and flexibility,” says Anil Joshi.

Buying tips

While making a purchase decision, one key factor should be kept in mind, that is, whether the product is the constant current type or constant voltage type.

It is very important to also consider the Indian climatic conditions. For use in India, this ballast must be designed for universal input, since the high voltage fluctuation can result in malfunctioning of the instrument.

The higher the efficiency, the lower the power consumption will be. If there is a huge gap between the output wattage of the ballast and input of power consumption, then the efficiency of the instrument is not much.

Other factors that one should look for are the low voltage and high voltage protection, and isolated and non-isolated technology. If one buys an instrument as per the requirements, then it can help in cutting power consumption.