Orb Optronix announced today the company will offer Pulse Width Modulation (PWM) and Single Pulse LED Characterization through its LED Test and Measurement Lab as standard testing services. PWM and Single Pulse LED Characterization services were previously offered as customized tests for customers. In response to requests from customers, these services have been automated and are now offered as standard tests.
Pulse Width Modulation is a common method of varying the amount of power delivered to an LED. By varying the duty cycle, or on-time, the LED output can be controlled. For general illumination or display applications, the pulses occur much faster than the eye will notice (100 Hz or faster). Orb Optronix PWM testing regimen allows sweeping of any one of duty cycle (pulse duration), pulse frequency, or LED drive current in conjunction with temperature to produce the parametric data sets necessary to optimize LED performance in a PWM controlled system.
Single Pulse LED Characterization allows a customer to gather comparative data by testing a device using single pulse NIST traceable measurements. The resulting measurements provide data for comparison of specific lots of LEDs to the specifications provided by LED manufacturers in their datasheets. These tests can also be used to generate comprehensive LED datasheets for manufacturers from an independent test lab.
The current industry standard of production testing LEDs with a single short pulse measures the basic features of LEDs for sorting purposes. These quick measurements are very practical for the manufacturer as the same fixture can test 20 or more LEDs per second. However, the measurements of an LED’s color, dominant wavelength, efficiency and forward voltage using the 25ms pulse method does not give realistic performance metrics for true use environments.
As more sophisticated LED applications such as dimming, color control and color mixing are introduced to the marketplace, LED Luminaire designers require testing that reflects more realistic use conditions. These LED characterization methods are critical to ensure LEDs are meeting manufacturer’s specifications, for “apples to apples” comparison of similar types of LEDs produced by different manufacturers and for statistical studies of large lots of LEDs for quality and consistency.