How to Read a Datasheet: LED Fundamentals

Post on 26-May-2015

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In this presentation on How to Read a Datasheet we will examine the key parameters specified on every page of an LED Datasheet from OSRAM Opto Semiconductors. The Datasheet captures some of the most important technical characteristics of an LED. These include electrical, optical and thermal quantities, knowledge of which is paramount for an LED system design. Also, it has information on ordering codes, labeling and packaging of the LEDs.

Transcript of How to Read a Datasheet: LED Fundamentals

LED Fundamentals

How to Read a DatasheetDatasheet (Part 1 of 2) Typical/Maximum Characteristics and Binningg

08-19-11

LED Parameters

Optical Quantities

Luminous Intensity IV Luminous Flux V

Electrical Quantities

Forward Voltage VF

Forward Current IF Luminance LV

Radiation Characteristics 2φ Dominant Wavelength dom

Color Coordinates c c

Reverse Current IR

Color Coordinates cx, cy

Thermal Quantities Misc

Junction Temperature Tj

Temperature Coefficient TC dom

Thermal Resistance RthJS

CRI Efficiency

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OSLON SSL (LUW CP7P)

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Ordering Information

Luminous Flux at binning current is listed in lumens (lm) or millilumens (mlm).

Luminous Intensity at binning current listed in candela (cd) or millicandela (mcd).

Example LUW CP7P-KSKU-5E8G-35 Example LUW CP7P-KSKU-5E8G-35

KSKU: One brightness group KS, KT or KU will be shipped for any one reel.

5E8G: One chromaticity group from 5E to 8G will be shipped for any one reel.

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35: One forward voltage group 3, 4, or 5 will be shipped for any one reel.

Maximum Ratings

Maximum permissible surge current for pulsed operation is defined by pulse duration, duty

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Maximum permissible surge current for pulsed operation is defined by pulse duration, duty cycle and frequency for a given solder point temperature (Ts).

Typical Characteristics

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Chromaticity Coordinate Groups

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Chromaticity Coordinates

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Brightness and Forward Voltage Groups

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Spectral Emission

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V is the human eye sensitivity curve

Radiation Characteristics

For OSLON SSL (LUW CP7P) the radiation curve hits the 50% line at (φ )40°

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Therefore the viewing angle (2 φ) is here equivalent 80°

LA CP7P

Peak wavelength

Wavelength with the highest emitted electromagnetic power

Dominant wavelength

Wavelength considering human eye sensitivity; defines the color we can see

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LED Fundamentals

How to Read a DatasheetDatasheet (Part 2 of 2) Characteristic Curves, Dimensions and ,Packaging08-19-11

Forward Voltage

Increase of forward voltage leads to higher current

For special applications, forward voltage grouping maybe necessary

• OSRAM offers voltage grouping

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• Each reel contains only one forward voltage group

Forward Current

The current through the LED determines the intensity/ flux output from the LED.

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Also, there is a slight variation in the color of the LED, depending on the LED current

Junction Temperature

As Junction Temperature increases

Forward Voltage decreases

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Luminous Flux decreases

Cx, Cy decreases

Maximum Forward Current

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Pulse Current

The maximum permissible pulse current depends on :

pulse duration

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p

duty cycle

Package Dimensions

LED is protected by ESD device which is connected in parallel to LED-Chip

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The notch on the thermal pad indicates the cathode pad

Tape and Reel

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Recommended Solder Pad Layout

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Soldering Profile

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Labeling/Tape and Reel

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Packaging

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Revisions

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Remarks

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Disclaimer

All information contained in this document has been checked with the greatest care. OSRAM Opto Semiconductors GmbH can however, not be made liable for any damage that occurs in connection with the use of these contents.

OSRAM Opto Semiconductor GmbH makes no representations and warranties as to a possible interference with third parties' intellectual property rights in view of products originating from one of OSRAM Opto Semiconductor GmbH's partners, or in view of products being a combination of an OSRAM Opto Semiconductor GmbH's product and a product of one of OSRAM Opto Semiconductor GmbH's partners Furthermore OSRAMproduct of one of OSRAM Opto Semiconductor GmbH s partners. Furthermore, OSRAM Opto Semiconductors GmbH cannot be made liable for any damage that occurs in connection with the use of a product of one of OSRAM Opto Semiconductor GmbH's partners, or with the use of a combination of an OSRAM Opto Semiconductor GmbH's product and a product of one of OSRAM Opto Semiconductor GmbH's partners.

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Thank you for your attention.Thank you for your attention.