Osram SYNIOS P2720 Application Note

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SYNIOS P2720 – General Information
Application Note Number: AN038
Application Note
Abstract
This application note provides insight into the LED product family of the SYNIOS P2720 (KxDMLy31). A basic overview of the construction, handling and processing of the SYNIOS P2720 is presented.
Content
1. Construction
2. Handling
3. Storage
4. Cleaning
5. Processing
Construction of the SYNIOS P2720
The product family SYNIOS P2720 is especially developed for use as small size light source with a wide range of operating currents, with its slim design suitable for a big variety of applications – from mid- to high-power.
The common package of the product family consists of an Au-plated lead frame and a white epoxy mold compound in which a highly efficient semiconductor chip is mounted and electrically connected (Fig1.).
Depending on the brightness requirements the SYNIOS P2720 is available in three different chip sizes (500µm, 750µm & 1000µm). The product group comprises the colors white, converted yellow, yellow, red and super red, whereas the red color group covers an extended wavelength range starting at λ The color coordinates of the white version (KWDMLy31.SG) is within the white field of UNECE/FMVSS.
The final encapsulation of the LED is silicone depending on the type either clear or converter filled. Figure 2 shows an overview about the available variants of the SYNIOS P2720 and their specific designation.
= 612nm to 628nm.
dom
Fig. 1: Design of the SYNIOS P2720
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Fig 2: Overview of SYNIOS P2720 family
Within the product family there are also differences in the ESD stability of the
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devices. In the versions white and converted
Application Note Number: AN038
yellow the LED features an ESD protection diode, which provides ESD stability of up to 8kV according to JESD22-A114-F (HBM). All other of the product group provides ESD robustness of 2kV.
Nevertheless as a matter of principle the common ESD safety precautions have to be observed during handling, assembly and production of electronic devices.
The common QFN-like design with identical solder pad layout and equal small dimensions (2.7mm x 2.0mm x 0.6mm) involves an additional benefit concerning design flexibility due to the exchangeability. With one circuit board layout, for example, several applications with different brightness requirements can be implemented. With the same layout either the brightness by different chip sizes can be adapted at the end of the development phase or later after some years. Also with the same board layout different requirements in brightness like for UNECE and FMVSS regulation can be fulfilled by the wide brightness range of the family for each color.
As a small LED without lens the SYNIOS P2720 is also perfectly suited for light guide applications.
As with all LEDs from OSRAM Opto Semiconductors, the SYNIOS P2720 product group also fulfills the current RoHS guidelines (European Union & China).
Handling
Accessorily to general guidelines for the handling of LEDs, additional care should be taken that mechanical stresses (e.g. sheering forces) to the elastic silicone encapsulation must be eliminated or reduced to the greatest extent possible (see also application note "Handling of Silicone Resin LEDs").
In general, all types of sharp objects (e.g. forceps, fingernails, etc.) should be avoided in order to prevent stress to or penetration of the encapsulation, since this can lead to impairment of the component.
Fig. 3: Manual Handling of the SYNIOS P2720
For manual assembly and placement – in the production of prototypes, for example – the use of so-called vacuum tweezers is recommended (Figure 4). The effective mechanical stress on the LED is minimized by individually exchangeable soft rubber suction tips.
Fig. 4: Examples of vacuum styluses
If there is no alternative to the exceptional use of a tweezers (anti-static), the LED must be picked and handled only at the epoxy housing (Figure 3).
Please note even after being soldered on the PCB board touching of the silicon must be avoided in order to avoid damages of the bond wire or of the LED housing. As it can be seen in Figure 5, the SYNIOS P2720 is packaged in tape and reel. When processing by means of automated placement machines, care should be taken
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to use an appropriate pick and place tool
Application Note Number: AN038
and to ensure that the process parameters are conform to the package's characteristics.
Figure 6 shows the recommended design of the placement tool for damage-free process­ing of the SYNIOS P2720.
Fig. 5: Position of the LED in the tape – method of taping
Fig. 6: Design proposals of the pick and place tool for the SYNIOS P2720 (dimensions in mm)
If possible, the tool should pick up the LED across the entire surface or along the
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package rim (Figure 7). The same applies when depositing or placing the LED. Forces
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should be applied over the entire surface or
Application Note Number: AN038
along the rim.
Fig. 7: Recommended pick-up area for SYNIOS P2720
Since the SYNIOS P2720 is generally supplied in tape with dry pack, it should be factory-sealed when stored. The hermetic pack should only be opened for immediate mounting and processing, after which the remaining LEDs should be repacked according to the moisture level in the datasheet (q.v. JEDEC J-STD-033B.1 ­Moisture Sensitivity Levels).
Storage
PCBs or assemblies containing LEDs should not be stacked such that force is applied to the LED, or should not be handled directly at the LED.
Fig. 8: Incorrect storage of LEDs
Generally, all LED assemblies should be allowed to return to room temperature after soldering, before subsequent handling, or the next process step.
Fig. 9: Correct storage of assemblies with LEDs
Cleaning
From today's perspective any direct mechanical or chemical cleaning of the SYNIOS P2720 is forbidden.
Isopropyl alcohol (IPA) can be used if cleaning is mandatory. Other substances or especially ultrasonic cleaning of SYNIOS P2720 are generally not recommended. For dusty LEDs, a simple cleaning by means of purified compressed air (e.g. central supply or spray can) is recommended here.
In any case, all materials and methods should be tested beforehand, particularly as to whether or not damage is associated with the component.
Notes concerning cleaning can be also found in the corresponding data sheets.
Processing
Generally, the SYNIOS P2720 product family is compatible with existing industrial SMT processing methods, so that current populating techniques can be used for the mounting process. The individual soldering conditions for each LED type according to JEDEC can be found in the respective data sheet. A standard reflow soldering process with forced convection under standard N2 atmosphere is recommended for mounting the component, in which a typical lead-free
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SnAgCu metal alloy is used as solder.
Application Note Number: AN038
Figure 10 shows the temperature profile for lead-free soldering with the recommended peak temperature of 245°C. In this context, it is recommended to check the profile on all new PCB materials and designs. As a good starting point, the recommended temperature profile provided by the solder paste manufacturer can be used. The maximum temperature for the profile as specified in the data sheet should not be exceeded, however.
When developing the circuitry, special attention should be given to the position and orientation of the LED on the circuit board. Depending on the position and orientation of the LED, the mechanical stress on the LED can vary. In general, it is recommended that all twisting, warping, bending and other forms
of stress to the circuit board should be avoided after soldering in order to prevent breakage of the LED housing or solder joints. Therefore, separation of the circuit boards should not be done by hand, but should exclusively be carried out with a specially designed tool.
For further information such as regarding PCB type, solder pad, solder stencil, voids, post reflow inspection and verification of the design please see also application notes “Processing of SMD LEDs”.
The SYNIOS P2720 features a good self alignment during soldering additionally supported by the four wetting indicators (Fig.
11).
Fig. 10: Temperature profile for lead-free reflow soldering according to JEDEC JSTD-020
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Fig. 11: bottom only-terminated contacts
Application Note Number: AN038
with wetting indicators
Fig 12 shows the LED before and after the IR soldering process.
Fig. 12: Self alignment of the SYNIOS P2720 during soldering
If a narrow LED clustering is requested in the application, please note a direct side by side contact between the housings has to be avoided due to the risk of short circuits.
Summary
The SYNIOS P2720 LED family is designed as small size high-flux light source. The design of the package enables the use of various chip sizes to satisfy different brightness levels and a wide range of operating currents as well.
With primary focus on automotive applications the LED is qualified based on the guidelines of IEC 60810, Lamps for road vehicles - Performance requirements. In addition the SYNIOS P2720 group features an improved corrosive robustness according to the following test conditions: 40°C / 90% rh / 15ppm H2S / 336h; = Stricter than IEC 60068-2-43 (H2S) [25°C / 75% rh / 10ppm H2S / 21 days] = Regarding relevant gas (H2S) stricter than EN 60068-2-60 (method 4) [25°C / 75% rh / 200ppb SO2, 200ppb NO2, 10ppb Cl2 / 21 days]). The relevant information can also be found in the datasheet of the LED product.
Currently the product group comprises the automotive preferred colors white, yellow, red and super red.
Generally supplied in tape and reel, the SYNIOS P2720 is compatible with existing industrial SMT processing methods, so that all customary populating techniques can be used for assembly.
It should also be kept in mind that the LED is not suitable for any direct mechanical or chemical cleaning.
During handling and processing mechanical stress to the silicone encapsulation must be reduced or eliminated to the greatest extent possible. Penetration of the silicone should be avoided. Either can lead to impairment of the component.
OSRAM Opto Semiconductors supports its customers during their development and design process in finding the best solution for a specific application.
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Appendix
Date
Revision History
Sept. 2014
Release application note
Application Note Number: AN038
Don't forget: LED Light for you is your place to be whenever you are looking for information or worldwide partners for your LED Lighting project.
www.ledlightforyou.com
Revision History
Authors: Andreas Stich, Norbert Häfner, Kurt-Jürgen Lang
ABOUT OSRAM OPTO SEMICONDUCTORS
OSRAM, Munich, Germany is one of the two leading light manufacturers in the world. Its subsidiary, OSRAM Opto Semiconductors GmbH in Regensburg (Germany), offers its customers solutions based on semiconductor technology for lighting, sensor and visualization applications. Osram Opto Semiconductors has production sites in Regensburg (Germany), Penang (Malaysia) and Wuxi (China). Its headquarters for North America is in Sunnyvale (USA), and for Asia in Hong Kong. Osram Opto Semiconductors also has sales offices throughout the world. For more information go to www.osram-os.com.
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Application Note Number: AN038
DISCLAIMER PLEASE CAREFULLY READ THE BELOW TERMS AND CONDITIONS BEFORE USING THE
INFORMATION SHOWN HEREIN. IF YOU DO NOT AGREE WITH ANY OF THESE TERMS AND CONDITIONS, DO NOT USE THE INFORMATION.
The information shown in this document is provided by OSRAM Opto Semiconductors GmbH on an “as is basis” and without OSRAM Opto Semiconductors GmbH assuming, express or implied, any warranty or
liability whatsoever, including, but not limited to the warranties of correctness, completeness, merchantability, fitness for a particular purpose, title or non-infringement of rights. In no event shall OSRAM Opto Semiconductors GmbH be liable - regardless of the legal theory - for any direct, indirect, special, incidental, exemplary, consequential, or punitive damages related to the use of the information. This limitation shall apply even if OSRAM Opto Semiconductors GmbH has been advised of possible damages. As some jurisdictions do not allow the exclusion of certain warranties or limitations of liability, the above limitations or exclusions might not apply. The liability of OSRAM Opto Semiconductors GmbH would in such case be limited to the greatest extent permitted by law.
OSRAM Opto Semiconductors GmbH may change the information shown herein at anytime without notice to users and is not obligated to provide any maintenance (including updates or notifications upon changes) or support related to the information.
Any rights not expressly granted herein are reserved. Except for the right to use the information shown herein, no other rights are granted nor shall any obligation be implied requiring the grant of further rights. Any and all rights or licenses for or regarding patents or patent applications are expressly excluded.
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