LED Driver Design Aspects

LED drivers are a critical component of any LED lighting system. They convert a higher-voltage alternating current (AC) to a lower voltage direct current (DC), which matches the Voltage requirements of each individual LED.

They also provide a steady current to prevent thermal runaway – a condition where LEDs overheat and burn out. In addition, they offer a wide range of output levels to meet different application needs and can be made with dimming capabilities for controlling the brightness of the light.

Brightness

Depending on the application, LEDs can produce various levels of brightness. For example, classrooms and warehouses benefit from bright white LED lights on the cooler end of the spectrum (5500-6000K) while wood toned interiors are more suited to warm natural white lighting (approximately 4000-4500K).

Many LED drivers offer more than one brightness level. Some even provide the ability to control brightness with a programmable feature.

One such feature is called “dimming” and allows the user to alter the brightness of an LED by controlling the amount of current that it receives from a power supply. This is typically accomplished using a “constant current reduction” technique, also known as analog dimming.

In addition, some drivers have “environment adaptive” features that allow them to boost the daylight led driver output voltage when necessary for short term operation at a low temperature. These features can give you 20% more “voltage head room” than a standard LED driver, which means the most amount of brightness possible from your LEDs. The most important part of all of this is selecting a driver that is suitable for your particular application. To help you with this decision, check out our LED Driver Selector Tool. It will guide you through the process of identifying a driver that is right for you and your project.

Color Temperature

The color temperature of an LED is a critical design aspect for a driver. The higher the color temperature, the more neutral a light will appear. 5000 K is a popular choice for LEDs used in driving applications because it provides a bright white light without the drowsy yellow tinge that can cause fatigue and affect road safety. This is also a great option for outdoor lighting where a low-wattage bulb is required.

Most daylight led drivers are programmable, meaning that they can be set to output any wattage you need by turning the voltage dial up and the current dial down. These drivers can also be voltage limited, which will reduce the power to the LEDs if they are accidentally disconnected. This is especially useful if you are using multiple LEDs in parallel, as the driver will not draw all the current at once.

In addition to programmability, most daylight led drivers have an adjustable resistor for dimming the incoming forward voltage. This is called a “current sensing resistor,” or “RS.” A fixed value for RS allows the driver to adjust its current in response to changes in the incoming voltage. The resulting output current is then equal to the forward voltage, which will result in uniform illuminance across the dimming range.

The Inventronics EUM and ESM series are a great example of these type of drivers. They offer a wide range of voltages (90-305Vac), output currents (90-500mA), and are Controls-Ready with 0-10V isolated dimming, Dim-to-Off and Always-On auxiliary power options.

Dimming

Dimming is a great way to control the light output of an LED. It allows you to adjust the intensity of the light, allowing for more comfortable, intimate lighting in restaurants or more vibrant, brighter lighting for a recreational setting.

The dimming of a daylight LED driver works by reducing the amplitude of current being fed to the LEDs, essentially mimicking the effect of a traditional incandescent bulb. It can be done either using pulse width modulation (PWM), analog dimming or a combination of the two.

Pulse width modulation dimming is a form of current control that uses a fixed time duration to change the average current. It’s the fastest method of dimming and can be used to reduce the output current to very low levels.

Analog dimming, on the other hand, uses a constant current and reduces the average current gradually. It’s typically the most effective dimming method and can be used to reduce the output current as low as a few hundredths of a volt.

Regardless of which dimming method is chosen, the most important thing to remember is that the current isn’t reduced as much as you may think. Rather, it’s fluctuated rapidly enough to create the illusion of diminishing light.

When you’re choosing a dimmer, make sure it’s compatible with your LED driver and can handle the voltage needs of the light. You can find this information on the specification table of a dimmer, or you can request one from the LED driver manufacturer.

For dimming to work properly, it’s important that the LED driver is loaded as close as possible to its rated maximum power output. This will allow the driver to provide a smooth and consistent dimming experience.

Some LED drivers can handle multiple dimmer types, so check to see if your new driver supports 0-10V DC dimming or digital addressable lighting interface (DALI). You can also find models that accept phase-control input.

A programmable LED driver will daylight led driver have an internal computer that connects to the dimmer, which can be set to adjust the output current, fade up time and dimming curves. This is a very convenient and flexible solution for outdoor applications such as streetlights, and it’s also a cost-effective alternative to traditional electronic dimmers.

Lifespan

The lifespan of an LED is one of the biggest selling points for the technology. Traditional lighting sources such as halogen lamps, incandescent bulbs and fluorescent tubes all have short lifespans that make them difficult to use for long periods of time.

The life span of an LED is characterized by the L70 standard rating which refers to the number of hours the LED can be used before its luminous flux has reduced to 70% of its original luminous output. This value is based on a study conducted by power LED industry group the Alliance for Solid-State Illumination Systems and Technologies (ASSIST).

Aside from evaluating an LED’s performance, it is also important to consider how the LED will be operated. The driver is an integral component to the LED and must be properly designed to ensure that the lifetime of the light source will match its specifications.

This includes the drive level and power supply, as well as the quality of the driver itself. Using an under-rated driver will reduce the lifespan of the light source, while overdriving it will cause heat generation and premature failure.

Drivers are typically made with electrolytic capacitors and are therefore heat sensitive; each 10degC increase in temperature will shorten their lifetime by half. The leakage rate of vaporized electrolyte from the capacitor is significantly accelerated when the internal operating temperature increases.

To avoid this problem, drivers should be run at operating temperatures below the junction temperature of the LED (referred to as the TC point), or they must include long-life electrolytic capacitors. If a driver is not able to meet these conditions, it will not last the lifetime of the LED and it will need to be replaced.

A high-quality driver will also have features such as a regulated voltage, forward current and LED drive level. These features will help to ensure that the driver is able to operate the LED safely and efficiently.

In addition, the driver should have a high level of heat and moisture resistance to ensure that it is not damaged by external factors such as humidity or dust. In this way, the driver will be able to function in a variety of environments and conditions.