Application Note

Light Emitting DiodeHow to Measure the Electrical
Characteristics of Luminaires
Using LEDs

Table of contents
1. Overview ..................................................................................... 2
2. Electric Energy Consumption/Luminaire Efficacyof the LED Luminaire ............................................................. 2
3. Typical Measuring Instruments .......................................... 3
4. How to Measure Electrical Characteristics with aDigital Oscilloscope ............................................................... 4
5. How to Evaluate with a Digital Power Meter .............. 12
6. Summary ................................................................................. 13

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Application Note
1. Overview
In recent years, LED luminaires have been replacing lighting devices using conventional technologies (e.g.
incandescent/fluorescent [CFL] lighting). White LEDs for general applications now have improved
luminous efficacies and it has led to an increased number of LED luminaires claiming to have highluminaire efficacies. As a result, when designing a luminaire it is very important for luminaire designers tolearn how to determine the electric power consumption (i.e. luminaire efficacy). This application note
provides information for this purpose with an emphasis on how to use an oscilloscope for electricalmeasurements.

2. Electric Energy Consumption/Luminaire Efficacy of the LED Luminaire
There are two different types of LED luminaires: those that contain internal power supplies and those that

Light Emitting Dioderequire external power supplies for operation. LED luminaires with an internal power supply include a
module mounted with LEDs (i.e. LED light engine) and a power supply circuit to convert alternating-current(AC) power to power that is suitable to operate the LEDs (i.e. AC/DC transformer/LED driver). There aremany different types of AC/DC switching power supplies: Typically, they convert AC current to DC current
with a bridging diode and increase/decrease the DC voltage with both a switching circuit and capacitor
at the same time; there are also other transformers that only perform switching from AC to DC. Regardlessof the type of AC/DC switching power supply, when AC current is converted to DC current and/or AC
voltage is changed from one voltage level to another, a power loss occurs in the power supply. The power
consumption at the lighting system level is the sum of the power used in the LEDs on the module and thepower lost in the power supply. In other words, if the power supply’s loss increases it causes the luminaire’s
power consumption to escalate, causing the luminaire efficacy to decrease. As a result, when designing
an LED luminaire, it is important to determine the power supply energy loss first and then choose theLED(s) and design the LED circuit.
Luminaire’s
Total Power Consumption
Electric Power Lost

AC

LED’s Power
Consumption

LED Light Engine

AC/DC Switching
Power Supply
Circuit

Luminaire’s Power Consumption = Electric Power Loss in the Power Supply + LEDs’ Power Consumption

Figure 1. Example of a LED Luminaire configuration

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Application Note
3. Typical Measuring Instruments
There are various approaches and instruments for measuring electrical characteristics (e.g. electric power).
All of these approaches and measuring instruments have advantages and disadvantages. For examples ofthese instruments and a summary of their advantages and disadvantages, refer to Table 1 below.
In the following sections, two different approaches for measuring electric power are discussed: the first
approach uses a digital oscilloscope and measures waveforms and calculates numerical values; the second
approach uses a digital power meter and determines numerical values. The methods discussed here areintended to be performed with standard types of digital oscilloscopes/digital power meters. However,depending on the type of instrument used, it may cause damage to the instrument/equipment and/or
danger to the user (e.g. electric shocks). Read the instructions/warnings for the instrument/equipment
carefully and operate them correctly as instructed.
Table 1. Instruments for Measuring Electrical Characteristics

Light Emitting Diode

Measuring Instruments1

Advantages

Disadvantages

Simple Electric Power‧ Easy connection‧ Limited to electric power

Meter‧ Inexpensive

measurement (Current/voltage‧ Excellent portability

measurement is not supported)

10 .0 W

‧ Low accuracy (trade-off for the
inexpensive price)
Digital Multimeter‧ Easy operation‧ Unable to determine the real

‧ Compact models available;

power in AC circuits (i.e. effective

excellent portability

voltage/current; however, power‧ Some can measure electricalfactor measurement is notcharacteristics (e.g. voltage,

supported)current, resistance)‧ The circuit must be disconnected
when measuring the current.

Digital Oscilloscope‧ Monitors the waveform‧ Expensive‧ Calculates electric power/power‧ Poor portability

factor by using the obtained
waveform data.
Digital Power Meter‧ Electrical characteristics (e.g.

‧ Complicated wiring

voltage, current, electric power,‧ Expensive

power factor, etc.) are displayed‧ Poor portability

in numeric values.
‧ Electric power consumption data
(e.g. accumulated electric power
consumption, electric power
consumption vs. time, etc.) aredisplayed in a graph.
Note:
1

The images are only for reference purposes.

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Application Note
4. How to Measure Electrical Characteristics with a Digital Oscilloscope
4.1. Digital Oscilloscope
The oscilloscope observes the change of an electrical signal (e.g. voltage, current, etc.) over time andpresents the waveform on the display in a graph. Analog oscilloscopes (i.e. cathode-ray oscilloscopes[CRO]) were previously widely used, though now have been almost entirely replaced with digital storage
oscilloscopes (DSO). DSOs are equipped with liquid-crystal display (LCD) panels and analog-to-digitalconverters (ADC), and store data in digital format. With these features, DSOs convert captured voltage
signals (i.e. voltage waveforms) to digital data via the converter to store in the memory and present thesewaveforms in numeric data. This allows DSOs to calculate effective values and average values; if thevoltage and current are measured at the same time via two different channels, it will allow the oscilloscope

Light Emitting Diodeto calculate the electric power consumption and power factor.
4.2. How to Select an Oscilloscope and Probe
4.2.1. DSO
Refer to Table 2 below for important items to consider when selecting a digital oscilloscope.
Table 2. Typical DSO Specifications
Items

Descriptions/Required Specifications

Number of

The number of channels that the device is capable of using for a measurement is an

Channels

important feature when selecting an oscilloscope. To determine electric power
consumption, the oscilloscope is required to measure the voltage waveform andcurrent waveform simultaneously. For this reason, the minimum number of channels
is two.

Bandwidth

It refers to the range between the upper and lower frequencies that an oscilloscope
can capture, typically measured in hertz. To capture/measure radio frequency signals
or signals with fast rise times, the bandwidth is an important factor to consider whenselecting an oscilloscope. As a general rule, the samples per second should be atleast 5 times higher than the bandwidth being measured for accurate
measurements; however, most of the oscilloscopes available in the market atreasonable prices these days have bandwidths over a few dozen MHz. As a result,
there will be no issues when using a general-purpose AC electric power supply (i.e.
typically operated on 50~60 Hz) for measurements.

Sampling rate

It refers to the frequency of the sampling input signals, measured in the number ofsamples per second. Typically, the samples per second rate should be at least 5
higher than the maximum bandwidth being measured; however, there will be noissues when using a general-purpose AC electric power supply (i.e. typicallyoperated on 50~ 60 Hz) for measurements.

Insulation Type

Typical oscilloscopes do not provide isolation from the ground (i.e. chassis ground)nor isolation between channels; the chassis and channels are electrically connected.
When measuring a signal with this type of oscilloscope, if the reference point tomeasure the waveform is a point other than ground or the potentials between theThis document contains tentative information, Nichia may change the contents without notice.
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Application Notechannels are different, it may damage the instrument and/or cause injury (e.g.
electrical shock). This can be avoided by either using a special type of oscilloscopewith channel-to-channel isolation and channel-to-ground isolation, or by using ahigh differential probe. For more details on high differential probes, see 2) High
Voltage Differential Probes below.
4.2.2. Current Probes
If an AC probe is used to measure AC current/voltage (e.g. main electric
power), it may cause the measurement to be inaccurate. In this case, AC/DC
current probes should be used. Ensure that a probe with sufficient capacity
is selected to measure the target signals (e.g. the maximum currents, peakcurrents, etc.). Additionally, when measuring a low current, it is important toLight Emitting Diodeconsider the oscilloscope’s sensitivity (resolution).

Figure 2.
Example of a Current
Probe4.2.3. High-Voltage Differential Probes
If the oscilloscope is a non-isolated input oscilloscope, depending on how
the instrument is used, it may cause damage to the instrument and/or
electrical shock. For this case, using a differential (isolated) probe enables
the oscilloscope and/or the other channels to be isolated to ensure safe
measurement.

Figure 3.
Example of a High-Voltage
Differential Probe

4.3. How to Use a Digital OscilloscopeThis section provides only basic instructions on how to use a digital oscilloscope. When using anoscilloscope refer to the manuals provided by the manufacturer for instructions on how to operate itproperly.
4.3.1. Calibration of the Oscilloscope
The oscilloscope and probes must be calibrated in order to ensure that the measurement is accurate andit should be done on a regular basis by an accredited laboratory.
4.3.2. Adjusting the Probe Settings
Passive probes are normally attached to oscilloscopes when purchased and the most common type ofprobes used with oscilloscopes typically have a 10:1 attenuation factor. For cases where other types ofprobes are used (e.g. current probes used when measuring current), the probe may have different
attenuation factors. In this case, it is important to use the proper attenuation factor for the measurement
and to ensure that the corresponding channel of the oscilloscope is correctly adjusted to match theattenuation factor. If the attenuation factors do not match between the probe and the corresponding
channel, it may cause measurement errors; ensure that the same attenuation factor that is appropriate forthe measurement is set on both the probe and oscilloscope sides.
Additionally, if a current probe is used continuously, the probe’s magnetic core will become magnetized
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Application Noteon a regular basis. Depending on the probe that is used, this can be done by pressing the button to
degauss when current is not applied to the measured item.
4.3.3. Adjusting the Horizontal and Vertical Settings
The range of the vertical axis (i.e. voltage) should be adjusted to enlarge the waveform to the maximum
level while ensuring that the high and low points of the waveform do not exceed the vertical range of the
field. If the range of the vertical axis is larger than it should be, it may cause the waveform to be difficult
for the oscilloscope to read (see Figure 5); if it is too small, the waveform may be cut off at the top andbottom (see Figure 6). In either case, the oscilloscope may not be capable of displaying numeric values
for the waveform due to these incorrect settings.
When setting the range of the horizontal axis (i.e. time), ensure that a sufficient number of wave cycles isdisplayed per measurement. If the range chosen is not sufficient, a correct waveform will not be formed

Light Emitting Diodeand it will cause the oscilloscope to fail to display numerical values (see Figure 7).

Figure 4.

Figure 5.

Normal waveform is displayed (AC100V/60Hz)

Range of the vertical axis is too large

Figure 6.

Figure 7.

Range of the vertical axis is too large

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Application Note
4.3.4 Adjusting the Trigger Settings
A digital oscilloscope stores digital data in its memory after capturing voltage signals and converting theminto digital data via the AC-DC transformer. Once the memory has reached full capacity, it will overwrite
the oldest recording on a first-in, first-out basis. This can cause the waveform displayed on theoscilloscope to be unstable (e.g. the waveform appears to jitter back and forth horizontally on theoscilloscope display). To control the recording of signals in the memory and acquire a static image of thesignals, the trigger function should be used and adjusted correctly.
The trigger settings can be adjusted by using trigger setting items, examples are listed in Table 3. If a
trigger event does not occur, adjust the trigger level and/or change the trigger type (e.g. Edge, Video,
Pulse, and Logic). If these settings are appropriate, then a valid trigger event occurs when a signal crosses
the trigger point defined by the trigger position and trigger level according to the other settings (e.g.

Light Emitting Diodetrigger type and slope).
Table 3. Trigger Setting Items
Items

Notes

Trigger Type

Select the shape of a waveform from several options (typically, “edge”, “pulse”,“video” and “logic”). When any waveform that matches a selected type is detected,
a trigger event occurs. Edge triggering is the basic and most common type. To
measure a typical AC waveform (see Figure 8), select the “edge” type.

SourceSelect sources (e.g. channels, external sources, etc.) used to trigger signals

Slope

For edge triggering, it is required to select an option from “rising slope” or “fallingslope” for the oscilloscope to trigger when a signal meets selected conditions (e.g.
If “rise” has been selected and a signal meets the selected conditions for the trigger
level at the rising slope, then a trigger event occurs).

Trigger Position

Set the horizontal position (i.e. time/horizontal axis) to trigger signals. To see theportion of a waveform captured before the point where triggering occurs, adjust
the trigger position horizontally for the captured waveform.

Trigger Level

Set a voltage level (i.e. voltage/vertical axis) to trigger signals. When a signal meetsset conditions (e.g. slope, trigger position, trigger level, etc.), then a trigger event
occurs.

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Application Note
Trigger Position

Type:

Trigger Level

Edge

ル

Slope:

Trigger Level

RisingルLight Emitting Diode

Since the signal reached the point on the rising slope
where both the trigger position and trigger level cross on
the display, a valid trigger event has occurred (this makes
the unstable waveform appear static).

Since the signal does not reach the point where thetrigger position and level cross, a trigger event has notoccurred (the waveform will continue to movehorizontally).

Figure 8.

Figure 9.

When a Valid Trigger Event has Occurred

When a Trigger Event Fails to Occur or is not
Applied4.4. How to Measure Electric Parameters with a Digital OscilloscopeThis section provides details on how to measure electrical parameters for AC power supplies using a digital
oscilloscope.
4.4.1. How to Connect to a Digital Oscilloscope with Peripheral Equipment

DSO
Voltage Probe

Current Probe
Power Supply

Measured Item

Figure 10. How to Connect to a Digital Oscilloscope (Example)

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Application Note
4.4.2. Measuring Effective Voltage/Current
Effective voltage and current can be represented by the following Equation 1 and Equation 2 respectively.
Digital oscilloscopes measure electricity according to a set sampling rate and store instantaneous values
recorded at set intervals in the memory and it allows the oscilloscope to display effective values that havebeen calculated by the oscilloscope itself immediately after measurements. If it is possible to retrieve
numerical data from the oscilloscope, then it will be possible to process the data on a computer by using
spreadsheet software.
When triggering a signal, if the captured waveform appears cut off on the top/bottom or the number ofthe periods on the display is not sufficient, it may prevent the oscilloscope from storing correct
instantaneous data; this may lead to incorrect numerical values being displayed on the screen. Adjust thehorizontal/vertical scales (i.e. time and voltage scales) to ensure that appropriate shape ofwaveform/number of the periods are displayed on the screen (The numbers of periods displayed on theLight Emitting Diodescreen should be integral numbers).
1

𝑇

𝐸𝑓𝑓𝑒𝑐𝑡𝑖𝑣𝑒 𝑉𝑜𝑙𝑡𝑎𝑔𝑒(𝑉) = √𝑇 ∫0 𝑣(𝑡)2 𝑑𝑡
wherev(t): Instantaneous voltage value,

1

T: Number of periods (the number of sample captured）

𝑇

Equation 2

𝐸𝑓𝑓𝑒𝑐𝑡𝑖𝑣𝑒 𝐶𝑢𝑟𝑟𝑒𝑛𝑡(𝐴) = √ ∫0 𝑖(𝑡)2 𝑑𝑡
𝑇

wherei(t): Instantaneous current value,

Equation 1

T: Number of periods (the number of sample captured）

Figure 11. How an Oscilloscope displays effective values on the screen (Example)
4.4.3. How to Measure Effective Power (i.e. Power Consumption)
Effective power (i.e. power consumption) can be determined by Equation 3 below. If voltage and current
signals are captured simultaneously, oscilloscopes can determine the effective power (i.e. power
consumption) by using the measurement results.
1

𝑇

𝐸𝑓𝑓𝑒𝑐𝑡𝑖𝑣𝑒 𝑃𝑜𝑤𝑒𝑟(𝑊) = 𝑇 ∫0 𝑣(𝑡)𝑖(𝑡)𝑑𝑡
wherev(t)i(t): Instantaneous electric power value,

Equation 3

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Application Note
1) The oscilloscope has used the math functions to multiply the instantaneous samplings of current andvoltage and displayed the results as instantaneous samplings of electric power in waveforms (i.e. the Mathwaveform in red).
2) Additionally, it has used the calculated power waveform and displays the average value (i.e. “10.2VA”
on the right side shown in the red box). This value is the effective power (power consumption).

Math:Light Emitting Diode

Average

CH1―: Voltage measured at channel 1
CH2―: Current measured at channel 2
Math―: Calculated value (instantaneous
power) as a result of CH1 x CH2

Figure 8. A Digital Oscilloscope Calculating/Displaying Effective Power (Power Consumption)
4.4.4. Apparent Power/Power Factor
In the case of typical AC/DC power supplies, a phase difference occurs between voltage and current due
to the reactive components of circuit elements used (e.g. capacitors, inductors, etc.). This phase difference
generates reactive power that does not contribute to energy consumption in a luminaire. The sum ofreactive power and effective power (i.e. actual electric power consumed in a luminaire) is referred to as
apparent power (see Equation 4).
Apparent power can also be calculated by Equation 5; with this equation it is possible to determine
apparent power by using effective values measured in section 2.4.2. Power factor refers to a value
representing the ratio of effective power to apparent power (see Equation 6). The larger this value is andthe closer it is to 1 (100%), the more desirable the power factor is for a power supply.
At an individual level, since only effective power is consumed by luminaires, even if the power factor ispoor and the reactive power is large, it will not cause the luminaire power consumption to increase. At a
facility level, however, a poor power factor may be an issue: the rated capacity of a facility (e.g. power
plant, etc.) is measured in apparent power; if a power supply with poor power factor is used, it will cause
the load on the facility to increase. To improve the power factor, there are cases where power factor
correction (PFC) circuits are used.
𝐴𝑝𝑝𝑎𝑟𝑒𝑛𝑡 𝑃𝑜𝑤𝑒𝑟(𝑉𝐴) = 𝐸𝑓𝑓𝑒𝑐𝑡𝑖𝑣𝑒 𝑃𝑜𝑤𝑒𝑟(𝑊) + 𝑅𝑒𝑎𝑐𝑡𝑖𝑣𝑒 𝑃𝑜𝑤𝑒𝑟(𝑣𝑎𝑟)

Equation 4

𝐴𝑝𝑝𝑎𝑟𝑒𝑛𝑡 𝑃𝑜𝑤𝑒𝑟(𝑉𝐴) = 𝐸𝑓𝑓𝑒𝑐𝑡𝑖𝑣𝑒 𝑉𝑜𝑙𝑡𝑎𝑔𝑒(𝑉) × 𝐸𝑓𝑓𝑒𝑐𝑡𝑖𝑣𝑒 𝐶𝑢𝑟𝑟𝑒𝑛𝑡(𝐴)Equation 5𝑃𝑜𝑤𝑒𝑟 𝐹𝑎𝑐𝑡𝑜𝑟 = 𝐸𝑓𝑓𝑒𝑐𝑡𝑖𝑣𝑒 𝑃𝑜𝑤𝑒𝑟(𝑊) / 𝑅𝑒𝑎𝑐𝑡𝑖𝑣𝑒 𝑃𝑜𝑤𝑒𝑟(𝑣𝑎𝑟)

Equation 6

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Application Note
4.5. How to Determine Power Supply Efficiency and Luminous Efficacy
To determine power supply conversion efficiency and power loss, measure the power consumption on
both the input and output sides (see Equations 7 and 8). To determine the luminaire efficacy, attach theoptics (e.g. secondary lens, covers, etc.) to the LED module and measure the system-level luminous fluxand input power (i.e. luminaire power consumption). To determine the LED luminous efficacy, remove theoptics from the LED module and measure the luminous flux and the output power of the LED module (seeEquations 9 and 10).
Accordingly, when evaluating the LEDs for the chosen application, measure the LED module without any
optics attached. If a part that can cause power loss is used on the same PCB, take this into consideration.
𝑃𝑜𝑤𝑒𝑟 𝑆𝑢𝑝𝑝𝑙𝑦 𝑃𝑜𝑤𝑒𝑟 𝐿𝑜𝑠𝑠(𝑊) = 𝐼𝑛𝑝𝑢𝑡 𝑃𝑜𝑤𝑒𝑟(𝑊) − 𝑂𝑢𝑡𝑝𝑢𝑡 𝑃𝑜𝑤𝑒𝑟(𝑊)Equation 7

Light Emitting Diode

𝑃𝑜𝑤𝑒𝑟 𝑆𝑢𝑝𝑝𝑙𝑦 𝐶𝑜𝑛𝑣𝑒𝑟𝑠𝑖𝑜𝑛 𝐸𝑓𝑓𝑒𝑐𝑖𝑒𝑛𝑐𝑦(𝑉𝐴)= (𝑂𝑢𝑡𝑝𝑢𝑡 𝑃𝑜𝑤𝑒𝑟(𝑊) / 𝐼𝑛𝑝𝑢𝑡 𝑃𝑜𝑤𝑒𝑟(𝑊)) × 100

Equation 8

𝐿𝑢𝑚𝑖𝑛𝑎𝑖𝑟𝑒 𝐸𝑓𝑓𝑖𝑐𝑎𝑐𝑦(𝑙𝑚/𝑊)= 𝐿𝑢𝑚𝑖𝑛𝑎𝑖𝑟𝑒 𝐿𝑢𝑚𝑖𝑛𝑜𝑢𝑠 𝐹𝑙𝑢𝑥(𝑙𝑚) / 𝑂𝑢𝑡𝑝𝑢𝑡 𝑃𝑜𝑤𝑒𝑟(𝑊)Equation 9

𝐿𝐸𝐷 𝐿𝑢𝑚𝑖𝑛𝑜𝑢𝑠 𝐸𝑓𝑓𝑖𝑐𝑎𝑐𝑦(𝑙𝑚/𝑊)= 𝐿𝐸𝐷 𝑀𝑜𝑑𝑢𝑙𝑒 𝐿𝑢𝑚𝑖𝑛𝑜𝑢𝑠 𝐹𝑙𝑢𝑥(𝑙𝑚) / 𝑂𝑢𝑡𝑝𝑢𝑡 𝑃𝑜𝑤𝑒𝑟(𝑊)Equation 10

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Application Note
5. How to Evaluate with a Digital Power Meter
5.1. Digital Power Meters
There are various types of instruments to measure electric power, ranging from ones that are inexpensive
and simple to use but limited in capabilities to ones that are expensive, multifunctional and excellent inaccuracy. Among these various types of watt meters, this section focuses on digital power meters (seeSection 3) and provides information on how to measure with a digital power meter. In addition to basic
features (e.g. instantaneous measurement/display of effective voltage/currents, power consumptions,power factors, etc.), some digital power meters are capable of providing advanced measurements (e.g.
peak value, crest factor, total harmonic distortion [THD], etc.). It is possible to select a digital power meterthat has the functions and degree of accuracy needed for the chosen application.

Light Emitting Diode5.2. How to Use a Digital Power Meter
5.2.1. Circuit Connection Examples
Input (AC)Output (DC)Input (AC)Output (DC)

L

+

L

+

③

AC/DC Switching
Power Supply

V

AC
① A ②

④

Digital Power
Meter

N

AC/DC Switching
Power Supply

AC
-

N

-

A
Digital Power
Meter

Please Refer to Figure 16 for ①-④.

Figure 13.
Measuring Luminaire Power
Consumption (Connecting to thepower supply on the input side)V

Figure 14.
Measuring Luminaire Power
Consumption (Connecting to thepower supply on the output side)

5.2.2. How to Connect a Digital Power Meter to Measure Luminaire Power Consumption
Digital Power Meter

①

②

③
④

Power Supply

Measured Item

Figure 15.
Digital Power Meter Connection Example

Wires (No.1 and No.2)
connected to a power
supply (see Figure 13 forthe schematic diagram)

Wires (No.1 and No.2)
connected to a power
supply (see Figure 13 forthe schematic diagram)

Figure 16.
Electrical connections on the back of a digital
power meter

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Application Note
5.2.3. How a Digital Power Meter Displays Measurement Results

Figure 17. Display of Measurement Results (Example)
Digital power meters display measurement result in numbers (see Figure 17). In the above example, thedigital power meter is displaying effective voltage (Display A), effective current (Display B) and effective

Light Emitting Diodepower (i.e. power consumption [Display C]); it can show other measurement results (e.g. apparent power[VA], power factor [PF], etc.) on these displays.

6. Summary
This application note only provides information of how to measure electrical power with an oscilloscopeand digital power meter (i.e. watt meter). There are many other types of instruments available for power
measurement. Consider the purposes/requirements and select the appropriate instruments for the chosen
application.

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Application Note

Light Emitting Diode

Disclaimer
This application note is a controlled document of Nichia Corporation (Nichia) published toprovide technical information/data for reference purposes only. By using this applicationnote, the user agrees to the following: This application note has been prepared solely for reference on the subject matters
incorporated within it and Nichia makes no guarantee that customers will see the same
results for their chosen application.
 The information/data contained herein are only typical examples of performances and/or
applications for the product. Nichia does not provide any guarantees or grant any licenseunder or immunity from any intellectual property rights or other rights held by Nichia or
third parties.
 Nichia makes no representation or warranty, express or implied, as to the accuracy,completeness or usefulness of any information contained herein. In addition, Nichia shallnot be liable for any damages or losses arising out of exploiting, using, or downloadingor otherwise this document, or any other acts associated with this document.
 The content of this application note may be changed without any prior or subsequent
notice.
 Copyrights and all other rights regarding the content of this document are reserved by
Nichia or the right holders who have permitted Nichia to use the content. Without priorwritten consent of Nichia, republication, reproduction, and/or redistribution of thecontent of this document in any form or by any means, whether in whole or in part,
including modifications or derivative works hereof, is strictly prohibited.

491 Oka, Kaminaka-Cho, Anan-Shi,
TOKUSHIMA 774-8601, JAPAN
Phone: +81-884-22-2311 Fax: +81-884-21-0148

NICHIA CORPORATION
http://www.nichia.co.jp

This document contains tentative information, Nichia may change the contents without notice.
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