This section about physical LED bulb properties found on the LED data sheets, contains very general but useful information about super bright LEDs. In some cases, portions of information contained within this section are redundant among various super bright LEDs produced by a specific LED bulb manufacture. For example, section 4 on the sample data sheet describes the recommended component orientation. This information would most likely apply to all surface mount LED bulbs produced by Nichia America. Graphical data presents a non-liner relationship between two light emitting diode characteristics. This allows a designer to perform very precise initial calculations during the design of a custom LED lighting design. This section provides more information than any other parts of the LED data sheets. After choosing a specific LED lamp for a new product design, the engineering team will typically refer only to graphical data throughout the rest of the design and engineering process.
For "initial optical / electrical characteristics" refer to previous section.
"Outline dimensions and materials" describes the general LED bulb composition including the LED lights outer package, encapsulating resin, and electrodes. Refer to Graphical Data on the LED data sheets for dimensional information.
"Packaging" outlines factory packaging procedures, box label format, and general shipping precautions. Such information is generally useful during preparation for ongoing or high volume super bright LED shipments. Refer to Graphical Data for depiction of LED bulb packaging.
"Lot Number" outlines light emitting diode lot number format describing the function of each character. Lot numbers provide specific information about the LED bulb such as date of manufacture, the manufacture's product number, and specific optical characteristics determined from factory testing. Recording the lot numbers during the circuit board assembly process enables future component tracking / tracing.
"Reliability" includes the results from numerous practical tests conducted by the LED lights manufacture and describes standard test procedures for determining if LED damage has occurred. The majority of tests represent relatively extreme operating environments with the exception of only several test items. It is important to understand that the LED manufacturer has established a control group in order to conduct testing. Individual LEDs do not undergo these specific tests.
"Cautions" outlines general precautions related to LED bulb packaging, storage, static electricity, system integration, assembly, maintenance, operation, human safety factors, applications, and general disclaimers. Portions of this information from the LED data sheets are generally common knowledge to those familiar with the numerous aspects of LED technology. However, this section does contain the recommended soldering pad design, reflow soldering profiles, and several other characteristics unique to this specific super bright LED.
Test items and results pertains to a series of tests and results, performed on the control group by the LED bulb manufacture. The "Test Item" column describes the nature of that specific test. The "Standard Test Method" column includes the "Japanese Electronic Industry Test Association" equivalent. The "Test Conditions" column offers some additional details about each specific test. Such details include information about temperature, time, material composition, humidity, and electrical characteristics. The "Note" column states additional test criteria such as time or number of cycles. Finally, the "Number of Damaged" column provides the actual test results.
Criteria for judging damage describes the method in which the LED bulb manufacturer determined the extent of damage to test subjects. It also offers the customer with a means for testing potentially damaged LED bulbs. The "Item" column states a specific light emitting diode property that may have varied due to damage. The "Symbol" column provides the industry standard symbol associated with the item in "Item Column". The "Test Conditions" column indicates the drive current utilized during testing. The "Criteria for Judgment" column indicates the minimum or maximum value to achieve in order for the LED manufacture to consider the LED bulb as damaged.
This data contains a series of detailed technical drawings related to the LED lights optical characteristics, electrical characteristics, component dimensions, tape and reel specifications, and packaging information. An engineer will frequently refer to the data contained within this section while performing major design calculations associated with the LED lighting application. Most of the information contained within this section contains data based on average values. It is important to remember that actual values may vary between lots. Obtaining measurements using calibrated electronic equipment is the only way to determine a true value. Also note that values may vary based on ambient temperature. It is very common for an engineer to perform calculations based on numbers located between numbers found on the graph itself. Interpolation is one method used to calculate a value somewhere between two corresponding values. However, for a more accurate method, increase the graph resolution by enlarging it to the size of your computer screen. Select the print option and choose "current view" to print a full sized image from your printer. Now you can easily measure and draw additional lines between existing values shown on the graph.
This diagram maps each color bin A through C as well as each sub-bin 0 through 8 on the CIE 1931 chromaticity diagram. All LED color bins correspond with an area found somewhere on this diagram. Color ranks using the A prefix indicate a color temperature between 9000 and 15000 degrees Kelvin. Color ranks using the B prefix indicate a color temperature between 5600 and 9000 degrees Kelvin, while color ranks using the C prefix indicate a color temperature between 4600 and 5600 degrees Kelvin. Specify a color rank before ordering, or refer to the second to last digit of the LED lot number to match the LED with a corresponding color rank. All information is subject to a measurement allowance of +/- 0.01.
The forward voltage vs. forward current depicts the relationship between LED drive current and the voltage drop measured across the super bright LEDs. This relationship is a property of the LED bulb itself, and provides an expectation as to how the LED will perform at various drive currents. You can see that the forward voltage increases with current. This information is extremely critical during circuit design. It is also apparent that the forward voltage is equal to 3.5 volts at 150 milli-amps. Note that this data corresponds directly with the forward voltage typical rating in the "Specifications" section under "Initial Electrical/Optical Characteristics".
Forward current vs. relative luminous flux depicts the relationship between LED drive current and the total luminous output. This relationship is a property of the LED lights, and provides an expectation as to how the LED will perform at various drive currents. On this graph, the relative luminous flux value of 1.0 refers to the typical luminous flux values previously stated in the "Specifications" section under "Ranking". To convert to a luminous flux value in lumens, simply multiply a previous value by a number from the relative luminous flux column in the graph. For example, the relative luminous flux of 0.5 is equal to 9 lumens from the P8 intensity bin. Note that the relative luminous flux is equal to 1.0 at 150 milli-amps. These values correspond indirectly with the typical luminous flux rating located in the "Specifications" section under "Initial Electrical/Optical Characteristics".
Duty ratio vs. allowable forward current depicts the relationship between the forward pulse current and the duty cycle (pulse duration divided by the period between each pulse). The relationship represents a limit, and not is a property of the LED itself. Many engineers refer to this graph as a derating curve, or more specifically, the duty-ratio derating curve. Exceeding the allowable forward current pulse can damage the LED. As you can see from the graph, duty ratio must decrease as the current is increased. This allows the PN junction within the LED to properly cool, therefore preventing permanent damage to the LED. You may also have noticed that the allowable forward current peaks out at the 10% duty ratio. This value corresponds with the absolute-maximum pulse forward current rating previously stated in the "Specifications" section under "Absolute Maximum Ratings".
Ambient temperature vs. forward voltage depicts the relationship between the forward voltage drop and the ambient temperature at various drive currents. This relationship is a property of the LED, and provides an expectation as to how the LED will perform at various temperatures. It is apparent from the graph that forward voltage will increase as the ambient temperature decreases. As temperature decreases, the LED operates more efficiently and generally produces a higher luminous output. It is also apparent from the graph that forward voltage also increases as the forward drive current increases. Note that at 25 degrees Celsius, 150 milli-amps, the forward voltage is equal to 3.5 volts. This value corresponds with the typical forward voltage rating previously stated in the "Specifications" section under "Initial Electrical/Optical Characteristics".
Ambient temperature vs. relative luminous flux depicts the relationship between the relative luminous flux and the ambient temperature. This relationship is a property of the LED lights, and provides an expectation as to how the LED will perform at various temperatures. Relative luminous flux corresponds with a value previously stated in the "Specifications" section under "Ranking". To convert from relative luminous flux to an actual value in lumens, multiply a previous lumen value by a number from the relative luminous flux column in this graph. For example, the relative luminous flux of 0.8 is equal to 14.4 lumens from the P8 intensity bin. As you can see from this graph, the luminous flux will increase as the ambient temperature decreases. This is because the LED operates more efficiently at lower temperatures, proving the importance of good thermal management. Also note that the relative luminous flux it 1.0 at 25 degrees Celsius, which indirectly corresponds with the luminous flux rating previously stated in "Specifications" under "Initial Electrical/Optical Characteristics".
Ambient temperature vs. allowable forward current depicts the relationship between the allowable forward drive current and the ambient temperature. The relationship represents a limit, and is not a property of the LED itself. Sometimes designers or engineers refer to this graph as the temperature-derating curve because it depicts how a drive-current derating becomes necessary as the ambient temperature increases. The LED must not operate outside of the specified area in order to prevent damage to the LED's die bond epoxy. At 25 degrees Celsius, the LED can operate safely up to 180 milli-amps. This was the maximum forward current rating previously stated in the "Specifications" section under "Absolute Maximum Ratings". Increasing the temperature beyond 25 degrees Celsius may result in a breakdown of the die-bond epoxy unless the forward current is derated. The dashed, solid, and dotted lines represent various thermal resistances from junction to ambient. This refers to the ability to transfer heat generated by the LED into the surrounding air. The external printed circuit board and heat sink ultimately affect the total thermal resistance (junction to ambient). As you can see from the graph, less efficient heat transfer requires derating at a much lower ambient temperature.
Forward current vs. chromaticity coordinate depicts the relationship between the drive current and chromaticity coordinate. This relationship is a property of the LED bulb, and provides an expectation as to how the LED lights will perform at various drive currents. The various points located on the graph represent different forward drive currents. As forward current increases, the chromaticity coordinate will decrease. As a result, the LED color appearance may slightly vary. At 150 milli-amps, the chromaticity coordinate X and Y are equal to 0.31 and 0.32, respectively. Note that these values correspond directly with the chromaticity coordinate previously stated in the "Specifications" section under "Initial Optical/Electrical Characteristics".
Spectrum depicts the LED's electromagnetic profile. As you can see from the graph, this specific LED features two dominate electromagnetic wavelengths. The first peaks just above 450 nano-meters, and the second peaks slightly above 550 nano-meters. The human eye perceives this combination of specific wavelengths as white light. Note that this specific super bright LED does not produce ultra-violet (UV) emissions.
Ambient temperature vs. chromaticity coordinate depicts the relationship between the ambient temperature and chromaticity coordinate. This relationship is a property of the LED, and provides an expectation as to how the super bright LED will perform at various temperatures. The points on the graph represent various temperatures of the surrounding ambient air. We can determine from the data that the chromaticity coordinate will decrease as the ambient temperature increases. On a previous graph, we determined that the chromaticity coordinate also decreased as the forward current increases. An increase in current always results in excess heat dissipation. Therefore, it makes sense that increasing forward current or temperature will cause a similar result on the chromaticity coordinate. You can see on this graph that the chromaticity coordinate at 25 degrees Celsius is equal to 0.31 / 0.32. This data corresponds directly with the data listed in the previous section, "Specifications", under "Initial Optical/Electrical Characteristics".
Directivity offers a profile depicting the specific shape of the super bright LED's light emissions. The left hand side of this graph depicts the relationship between the relative illuminance and the beam radiation angle. At the 0-degree mark, the relative illuminance is equal to 1.0, and the LED's beam is most intense at this point. At the 60-degree mark, the LED bulb's beam is only half as intense when compared to the brightest region, commonly referred to as the half angle.
Outline dimensions depicts the physical outline of the LED bulb package. This information is helpful during board layout and for general application design procedures. An internal LED schematic below the outline dimensions offers a basic circuit diagram of the LED bulb internally. The protection device helps guard against static discharge. However, an additional means of static protection provides the additional necessary protection during LED handling. In the bottom left hand corner, the materials table provides a basic description of the LED's composition.
Packaging information offers specific details about the LED tape and reel as well as the external packaging. Such information is generally useful while planning for larger assembly runs over an extended period. Specific tape dimensions provide information about compatibility with automatic placement equipment as well as component counting equipment. Most of the information within this section should be self-explanatory.