Strategy Marketing TeamSAMSUNG Electronics

COB (LC013B, LC026B, LC040B)

IndexIndex

1. Introduction 1

General structure of luminaire

2. Precautions 2

3. Assembly Process 3

① Preparing Wire

② Soldering Wire

③ Fixation of COB

1

Why mechanical guideline is needed ?

The COB itself could be assembled onto the substrate or lighting fixture. Therefore, they generally don’t need any automatic surface mounting process.

The below figure shows several key components, which are basic and important in a LED lighting. These parts are , in most cases, to be manually assembled by hand. During the manufacturing it is likely to have a more potential failure than that in an automatic process. And therefore, the mechanical guideline (for example install guide) should be very helpful to manufacture the lighting luminaires.

In this document, the mechanical guideline are available for assembling a lighting fixture using Samsung COBs.

- Precautions for mechanical treatment of Samsung COB

- Assembling procedure to be recommended

General structure of LED lighting

The lighting is mainly composed of three major core parts like a heat sink, a power supplier and lighting part (lighting source and 2nd optic components like a lens , reflector and diffusing plate). The COB is most important lighting source, which perform on the basic lighting and electrical characteristics. Heat sink is closely related with the operation conditions of COB, which may influence on the degradation of luminous properties in lighting. So it is very important to design a optimum heat sink and to attach COB to a heat sink for good heat dissipation.

Example of lighting fixture Including COB

Reflector

Diffusing plate

Screw and Washer

Electrical Wire

Thermal Interface Material

Heat Sink

COB

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2. Precautions

Handling COB

① Users have not to touch the lighting emitting surface(LES) in any cases.

② Users have to wear the anti-static gloves or anti-static wrist band.③ When handling COB, user have to use the anti-static tweezers.

(Especially, a sharpened-tip of the tweezers would have high possibility of giving a physical defect to COB)

④ When switching on COB with an electrical power supplier, an unexpected or abrupt current should bring about EOS failure in COB. This may also bring about the failure in use or the decrease of life time of products. Please discharge the stored voltage of the power supplier.

Chemical compatibility

During manufacturing luminaire, the many chemicals could attack and contaminate COB. It is necessary to avoid the contaminants and chemicals in manufacturing process and operation. And we are providing the guideline for chemicals and relevant failure mode.(Refer to chemical guideline).

All users have to read these precautions before handling Samsung COBs.

Bending COB

① Because the substrate material of COB is aluminum alloy, it is easy to be plastically deformed by a physical force. Although COB is mounted on heat sink or lighting fixture, users have to avoid any unnecessary forces which can bring about any strain.

②The site for fixation of COB have to be flat, smooth and clean surfaced. ③ When fixing COB onto a fixture, the pressure should be uniformly put on COB.

Contamination and cleaning

In the production of luminaire, COB can be contaminated by an unexpected contaminant. The organic material like as solder flux have to be cleaned out by using the tip of cotton swap soaked isopropyl alcohol(IPA).

Environment of Working place

The working area for assembly luminaire is recommended to be maintained clean for preventing any contamination and keeping workers’ safety. If all working area cannot be maintained clean, at least the space for assembly have to be kept clean

At LES (Lighting Emitting Surface), the resinand phosphor cannot protect the bondingwire from deformation or disconnection byan external force

The sharp tip may physically damage the resin of LES

3

Assembling process by using COB

In order to bond COB onto an heat sink or luminaire, the fixation generally proceed in two steps. First step is soldering a wire to COB. The second step is attaching COB onto the fixture. In this document, the manual wire connection and fixation are described in order.

General Procedure

- Cutting the wire at length needed- Peel off the tip of wire and connect wire to COB- Assembling(Attaching) COB onto Heat sink (Lighting Fixture)- Inspection

① Preparing Wire

: Before connecting wire, wire have to be prepared at the length needed according to the right methods. The thickness of wire is mainly dependent on the assigned maximum ampere. The below table is available to select the optimal wire thickness with the maximum ampere ratings.

In order to strip the end of wire, the optimal tool and method should be used for the safe and stable operations.

AWG Area (㎟) Assigned maximumAmpere rating (A) Prepared Cable

19 0.653 1.800

20 0.518 1.500

21 0.41 1.200

22 0.326 0.920

23 0.258 0.729

24 0.205 0.577

25 0.162 0.457

26 0.129 0.361

Amperage vs. wire size of copper conductor from UL486E

AWG26-19 (0.129~0.653 ㎟)

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② Soldering wire

For COB , it needs to be directly wired by soldering electrical wire.

- Considered Materials

It is most important to select the good materials for soldering. This would give an effect on the performance and reliability of lighting. And this will be eventually related with the life span of products

▪ Solder material : the soldering wire is recommended to be pb-free solders.

▪ Soldering flux : Using the soldering flux have to be carefully done so as not to leave a lot of flux residue. And after soldering, the residue of flux must be removed by isopropyl alcohol

- Wire connection procedure

Flux dispensing → Alignment of Wire → Soldering → Cleaning

▪ In process of flux dispensing, the optimum amount of flux must be carefully dispensed only on the electrode

▪ Wire orientation have to be determined on the structure of luminaire

▪ Soldering have to be done with optimal amount of solder. The below figure shows the good example of soldering with the amount of solder.

▪ After soldering, the excess flux, dirt and other contaminants should be removed with cotton swap and isopropyl alcohol(IPA).

Flux dispensing Soldering

In line wire orientation Parallel wire orientation

(a) Minimum amount

(b) Optimal amount

(c) Excess amount

Assembling process by using COB

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3. Assembly Process 3. Assembly Process _ _ ③③ Fixation of COBFixation of COB

- Using holder for COB

③ Fixation of COB

This chapter depicted the how to fix COB at the predefined site. Although many fixation methods can be treated, the two basic method will be mentioned in the point of cost and convenience. The first is using the fixation screw, the second is using the holder, which are provided by holder makers.

- Using fixation screw

This COB could be fixed by fastening 2 pairs of screw and washer. The concaved corner is adequate shape for fixing COB with screws of M4. As shown in below figure, the two of 4 corners, which is just for fixing screw. The size of screw and hole is recommended in below table.The 2 corners close to electrode pads should not be allowed to fix screw. It is highly possible to

bring about the electrical shortage . The torque for fixing screw is recommended to be 0.7~1.0 N∙m.

The using the holder is very convenient way to fix COB, to connect wires and to attach 2nd

optics like reflectors. Most features of holder are that the holder makes the electrical connection without soldering. This means that there is no need for a hot plate and for ventilation duck for exhausting fume.

Considering holders, the luminaire is consisted of the key parts like as shown in below figures. As described earlier, three main parts could be functioned as thermal, optical and electrical. The holder play the role which can connect all key parts so as to perform the their functions. This means that the holder is very simple way to fix the COB or to manufacture the luminair.

Screw size Washer sizeScrew Hole

size

M4 M4 4.7± 0.1mm

Screw2 Screw 1

Flat washer

Screw

Lock washer

[Source : TE ‘type Z50 LED holder Brochure for Samsung COB’]

Heat Sink TIM LED Holder ReflectorFixation method

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Date Revision History

2013.09.15 New Version