pwb handbook[1]

8/4/2019 PWB Handbook[1]

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UL CERTIFICATION

APPLICATION GUIDE FOR

PRINTED WIRING BOARD

UL( Version 2.0 )


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1

CONTENT

INTRODUCTION ........................................................................................................................... 2

Chapter I Process of Applying UL Certification for PWB PWB UL ................ 3

Chapter II Common-used GLOSSARY of PWB ............................. 4

Chapter III BOM Preparation of Rigid PWB ....................... 7

Chapter IV COMMON TEST ITEMS ......................................................... 17

Chapter V SAMPLE PREPARATION ..................................................................... 21

Appendix I Attachment I.......................................................................................................... 27


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2

INTRODUCTION

This handbook is the guide to help you to understand UL cert ification procedure clearly for PWB category. You can

understand them by reading from Chapter 1 to Chapter 5. Please use this for your application.

ULUL

By the handbook, we hope that you can adequately prepare for BOM and the samples to increase the nicety of information

collection and sample preparation.

()

UL standards for PWB certification:

UL

o UL 796 Printed-Wiring Boards

UL 796

o UL 94 Tests for Flammability of Plastic Materials for Parts in Devices and Appliances

UL 94

o UL 746E Polymeric Materials - Industrial Laminates, Filament Wound Tubing, Vulcanized Fibre, and Materials

Used in Printed Wiring Boards

UL 746E

o UL 746F Polymeric Materials - Flexible Dielectric Film Materials For Use In Printed-Wiring Boards and FlexibleMaterials Interconnect Constructions

UL 746F

If you have another question, please feel free to contact us.

,

Thank you for your cooperation.


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Chapter II Common-used GLOSSARY of PWB

2.1 BASE MATERIALAn insulator, consisting of organic or inorganic material that supports a pattern of conductive

material.

2.2 BUILD-UP THICKNESSOverall thickness of a combination of materials. Unless otherwise indicated, the build-up thickness will refer to the overall thickness of a board construction where no internal or external conductor

material resides.

2.3 SINGLE LAYER BOARDA PWB with only one layer laminate, may include single sided copper and double

sided copper. And in UL, we differentiate them into single layer single sided and single layer double sided., UL,

2.4 EDGE CONDUCTOR A conductor parallel with and spaced not more than 0.4 mm (1/64 inch) from the edge of aprinted-wiring board.

0.4mm

A 0

0.4mm

A


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2.5 IMMERSION SILVERConsists of a very thin coating typically less than 0.55 microns (0.0217 mils) of nearlypure silver created by galvanic displacement and may contain a slight amount of organic material deposited with the

silver.

0.55

2.6 MAXIMUM OPERATION TEMPERATURE The maximum temperature the board will be exposed to in the endproduct during operating conditions.

2.7 MIDBOARD CONDUCTORA conductor spaced more than 0.4 mm (1/64 inch) from the edge of a printed-wiringboard. Different with the Edge Conductor.

0.4mm

2.8 DELAMINATIONA planar separation of materials (i.e. separation between conductor and base material, prepreg,dielectric material, etc.).

2.9 SOLDER LIMITS: maximum temperature and time subjected during soldering process for component mounting.

But NOT solder application process during PWB manufacturing.

2.10 MAXIMUM AREA DIMETERShortened form is MAD, means Maximum unpierced conductor area

measurement

MAD,,

A PWB;

B Largest unpierced conductor section.

;

E Largest circle that fits B (the area is not to

exceed that of circle E in Figure). B

E


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2.11 UL 94 Flame Class: degree of flammability of the material

UL94

2.12 Minimum Copper ThicknessMinimum amount of copper for conductor lines or planes.

2.13 Meet UL 746E DSR: Direct Support Requirements are reference in Table 9.4 of UL 746E. These requirementsrelate to the ability of the material to support parts directly onto its surface that carry electrical current. Direct

Support value is based on the Individual laminate recognition.

UL746E Direct Support Requirements() UL 746E 9.4

DSR

2.14 CTI: Comparative Tracking Index is a property of electrical resistance of a material wetted with ionic solution.CTI

value are based on the Individual laminate recognition

CTI CTI


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7

Chapter III BOM Preparation of Rigid PWB

3.1 PWB

3.1.1 Single Layer PWB:SS

DS PW B

3.1.2 Mass Laminated PWB :

ULMass Lamination

PW B

3.1.3 Multilayer PWB:P WB

LaminatePrepreg

PWB

3.2

3.2.1 Typical BOM for Single Layer PWB /

Table 1. Desired Parameter for PWB. 1..

Your Desired PWB Parameters

1. PWB Type Designation

2. Minimum Thickness PWB ______mm

a. Maximum ______mic3.

Copper

Thickness

b. Minimum ______mic

4.Number of Cladding Sides (Single or Double)

5.Maximum Operating Temperature (

oC)

______ oC

a. Temperature (o C) ______ oC6.

SolderingLimits

b. Time (seconds) ______sec

a. Minimum Midboard Conductor Width ______mm

b. Maximum Unpierced Area Diameter

______mm7.

Pattern

Limits

c. Minimum Edge Conductor Width

______mm

8.Manufacturing Process Designation (e.g. A or B)

A B

9. UL 94 Flammability Class


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8

REMARKS

BOM Sheet (

):

1. PWB Type Designation:

Please fill the type designation in the blank, and note that please dont use ANSI grade or flame rating as

the PWB Designation.

UL/ANSI GradeFR-4,V-0

2. Minimum Thickness PWB :

The required minimum PWB thickness is not the minimum thickness of the laminate, but the minimumPWB thickness you have capability to produce through your manufacturing process, which is always not

less than minimum laminate thickness. The minimum thickness of PWB is measured without any copperand/or plating.

PWB

3. Copper Thickness:Please use mic (micron) as unit when measuring copper thickness;

mic () 1oz 34

4. Number of Cladding Sides (Single or Double) :Please follow your requirement, fill in single sided or double sided.

SSDS

5. MOT :

, ( 90o C, 105oC,130oC ),

PWBMOTMOT

6. Solder Limits ( ): Solder limits is the operating condition used in PWB assembly. Normally, Solder Limits

may be 260oC300oC / 5s~30s.

PWBSolder Limits 260oC300oC / 5s~30s

7. Pattern Limits ( ):

Minimum Edge Conductor Width should be no less than the Minimum Midboard Conductor Width, and no morethan three times of Minimum Midboard Conductor Width. When an edge conductor is not provided with a width of

less than three times the minimum width of a midboard conductor, or the required Minimum Edge Conductor cannot be provided (the distance from the board edge should be from 0 to 0.4mm, but should not be sheared along the

board edge), then the board shall be assigned an edge conductor width at three times the minimum midboardconductor width. If no conductor width is provided in this sheet, they will be given based on the actual measurementof UL Lab. Normally, Maximum Unpierced Area Diameter (MAD) may be 25.4mm, 38.1mm, 50.8mm, 76.2mm,

etc. And please refer to 2.10 to view the definition of MAD.

3

UL (

0.4mm ), ,MAD 25.4mm, 38.1mm,

50.8mm, 76.2mm MA D 2.10

8. Manufacturing Process Designation ()


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No special requirements, normally client would use A, B, C, and you should provide the specified manufacturing

steps. Please find the typical process for single layer PWB for your reference.

A B C

Example of Single-layer Manufacturing Process/ - 1

1. May cut, apply etch resist, may dry at _____C maximum for _____ maximum.

, ,, ______, _______

2. May etch in any etchant, except chromic/sulfuric.

3. May wash, remove etch resist, and dry at room temperature. ,,

4. May plate with nickel or gold. 5. Non-flame rated and HB -rated boards may be coated with any solder resist. V-rated Types may be coated

with only the resists indicated in the following pages. Boards may then be dried at _____C maximum for

_____ maximum.

,______, _______6. May punch, clean, and flux coat. ,

7. No other plating operations performed and no other temperature greater than 100oC encountered.

100oC

Example of single-layer Manufacturing Process/ - 2

1. May cut boards.

2. May drill and debur boards.

3. May electroless plate copper over through holes or entire board.

4. May scrub boards.5. May print pattern by silk screening or laminate dry film at _____ C maximum for _____ maximum.

,______, _______

6. May electroplate copper, then electroplate tin-lead.,

7. May strip plating resist.

8. May etch using any etchant except chromic/sulfuric.

9. May strip tin -lead.

10. Non-flame and HB rated types may be coated with any solder resists. V rated types may be coated with the

resists indicated in the following pages. Boards may then be dried at ___ __C maximum for _____

maximum.

,______, _______

11. May apply marking ink, and cure at _____C maximum for _____ maximum.

,______, _______12. May apply solder using hot air solder level at ___ __oC maximum for _____ maximum. ,

______, _______

13. May electroplate nickel and then gold on contact fingers or entire pattern.

/

14. May perform punching or routing.

15. May wash boards and dry at _____oC maximum for _____ minutes maximum.

, ______, _______

16. May apply flux.17. No other plating operations performed and no other temperature greater than 100

oC encountered.

100oC

Remarks Process Description ():


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a. Please select the appropriate manufacturing processes (single side PWB or double sid es PWB), and

nominate the process correctly, such as process A, B, C and etc. (single sided PWB

double sided PWB), Process A, B ,C

b. Please delete the steps you dont use from the standard process we provide.

c. Please guarantee the consistency between the Chinese and English when you provide the parameters with

both of them, such as the temperature and the dwell time.

d. Please provide your actual process. If the standard process we provide cant cover your actual process,

please add the related steps both in English and Chinese. ;

, ()

9. UL 94 Flammability Class : Please provide UL94 Flammability Rating which you desired, such as V-0, V-

1, V-2 and HB, etc .

V-0,V-1,V-2,HB

Table 2. Laminate Used for Single Layer PWB

2.

Single Layer PWB Type ()

Laminates Used ()

No.Laminate Designation

UL File No.

ULLaminate Mfr

ANSI Grade

ANSI

1.

2.

Base Material : Please provide the information of laminates used in your PWBs in PWB Material List Table,including Manufacturers name, related UL file No., laminate designation and UL/ANSI grade. If there is more than one

PWB designation, please make sure the laminates are in accordance with the related PWB designation.

UL

ANSI PWB PWB


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Table 3. Solder Resists Used for Single Layer PWB

3.

Single Layer PWB Type ()

Solder Resists Applied ()

No.Designation

UL File No.

ULSolder Resists Mfr

Color

1.

2.

Solder Resist(s) Please provide the solder resists used in your PWBs in PWB Solder Resist List Table. If there ismore than one PWB designation, please make sure the solder resists are in accordance with different PWB designations.

PW B

PWB

3.2.2 Typical BOM for Mass Laminated PWB /

Table 4. Desired Parameter for Mass laminated PWB

4. .

Your Desired PWB Parameters


2. Minimum Thickness PWB ______mm

a. Maximum ______mic3.

Copper

Thickness

b. Minimum ______mic

4.Number of Cladding Sides (Single or Double)

5.Maximum Operating Temperature (

oC)

______

oC

a. Temperature (oC) ______ oC

6.

Soldering

Limits

b. Time (seconds) ______sec

a. Minimum Midboard Conductor Width

______mm


______mm7.

Pattern

Limits


______mm


A B


Table 5. Laminate Used for Mass Laminated PWB.


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5.

Mass Laminated PWB Type ()

Laminates Used ()

No.Laminate Designation

UL File No.

ULLaminate Mfr

ANSI Grade

ANSI

1.

2.

Base Material : Please provide the information of laminates used in your PWBs in PWB Material List Table,

including Manufacturers name, related UL file No., laminate designation and UL/ANSI grade. If there is more than one

PWB designation, please make sure the laminates are in accordance with the related PWB designation.UL

ANSI

Table 6. Solder Resists Used for Mass Laminated PWB

6.

Mass Laminated PWB Type ( )


No.Designation

UL File No.

UL

Solder Resists Mfr

Color

1.

2.

Solder Resist(s) Please provide the solder resists used in your PWBs in PWBSolder Resist List Table. If there is

more than one PWB designation, please make sure the solder resists are in accordance with different PWB designations.

PW B

PWB


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Example of Mass Laminated PWB Manufacturing Process

(, )

1 May cut boards.

2 May drill and debur boards.

3. May electroless copper plate.

4. May scrub boards.

5. May print pattern by silk screening or laminate dry film at _____C maximum for _____

maximum.,_____C,_____


7. May strip plating resist.

8. May etch using any etchant except chromic/sulfuric.

9. May strip etch tin-lead.10 Non-flame and HB rated types may be coated with any solder resists. V rated types may be

coated with the resists indicated in the following pages. Boards may then be dried at _____C

maximum fo r _____ maximum.

,_____C, _____

11. May apply marking ink, and cure at _____C maximum for _____ maximum.

,_____C, _____

12. May solder reflow using hot air solder level at _____oC maximum for _____ maximum. ,

_____C,_____

13. May electroplate nickel and then gold on contact fingers or entire pattern.

/14. May perform punching or routing.

May wash boards and dry at _____

o

C maximum for _____ maximum., _____C,_____

15. May apply flux.

16. No other plating operations performed and no other temperature greater than 100oC

encountered.

100oC


a. Please complete the manufacturing process for multilayer PWB, and nominate the process correctly, such as

process A, B, C and etc. , Process A, B ,C

Please delete the steps you dont use from the standard process we provide.

.

b. Please guarantee the consistency between the Chinese and English when you provide the parameters with both ofthem, such as the temperature and the dwell time.

c. Please provide your actual process. If the standard process we provide cant cover your actual process, please

add the related steps both in English and Chinese. ; ,()


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3.2.3 Typical BOM for Multilayer PWB /

Table 7. Desired Parameter for Multilayer PWB

7.

Your Desired PWB

Parameters


2. Individual Laminate Layer Minimum Thickness ______mm

3. Individual Prepreg Layer Minimum Thickness ______mm

4. Total Build -Up Minimum Thickness ______mm

a. External Maximum (oz) ______mic

b. External Minimum (oz) ______mic

c. Internal Maximum (oz) ______mic5.

Copper

Thickness

d. Internal Minimum (oz) ______mic

6. Maximum Operating Temperature (oC) ______

oC

a. Temperature (oC) ______

oC

7.Soldering Limits

b. Time (seconds) ______Sec

a. Minimum Conductor Width

______mm


______mm8.

Pattern Limits


______mm


A B


REMARKS BOM Sheet ():

Total Build-Up Minimum Thickness : The required minimum PWB thickness is not the minimum

thickness of the laminate, but the minimum PWB thickness you have capability to produce through your manufacturingprocess, which is always not less than minimum laminate thickness. The minimum thickness of PWB is measured without

any copper and/or plating. And please refer to ATTACHMENT T3 to view some regular PWB thickness based on different

ANSI Grades.PWB

5.5 ANSI Grade


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Table 8Laminates and prepregs Used for Multilayer PWB

8.

Multilayer PWB type ()Laminates and Prepregs Used ()

No.Laminate/Prepreg Designation

UL File No.

Laminate /Prepreg Mfr

/

ANSI Grade

ANSI

Laminate:

1.Prepreg:

Laminate:2

Prepreg:

For Multilayer PWB, we will use laminate and prepreg together as a combination.

Table 9. Solder Resists Used for Multilayer PWB

9.

Multilayer PWB Type ( )


No. Designation UL File No. UL Solder Resists Mfr Color

1.

2.

Example of Multi-layer Manufacturing Process

1. May cut boards.

2. May image for innerlayer; laminate dry film at ___C maximum for _____ maximum

, ___C,_____.3. May etch using any etchant except chromic/sulfuric.

4. May strip etch resist, rinse and dry. , 5. May apply black oxide treatment.

6. May dry at ______ C maximum for ______ maximum.

,___C, _____

7. May laminate boards at _____C maximum for _____ maximum at a lamination pressure of

_____ PSI maximum.

,___C, _____,_____PSI.8. May dry at ______ C maximum for ______ maximum.

,___C, _____9. May cut, drill and debur boards. ,

10. May electroless copper plate.

11 May scrub boards.


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12. May print pattern by silk screening or laminate dry-film at _____ C maximum for _____

maximum.

,___C,_____.


14. May strip plating r esist.

15. May etch using any etchant except chromic/sulfuric.16. May strip tin-lead.

17. Non-flame and HB rated types may be coated with any solder resists. V rated types may be

coated with the resists indicated in the following pages. Boards may then be dried at _____C

maximum for _____ minutes maximum.

,___ C,_____

18. May apply marking ink, and cure at _____ C maximum for _____ maximum.

,___ C, _____

19. May solder reflow using hot air solder level at _____ C maximum for _____ maximum.,___ C, _____

20. May electroplate nickel and then gold on contact fingers or entire pattern. /

21. May perform punching or routing.

22. May wash boards and dry at _____C maximu m for _____ maximum.

, C_____

23. May apply flux.24. No other plating operations performed and no other temperature greater than 100 C

encountered. 100 C


Please complete the manufacturing process for multilayer PWB, and nominate the process correctly, such as process

A, B, C and etc. , Process A, B ,C

Please delete the steps you dont use from the standard process we provide.

Please guarantee the consistency between the Chinese and English when you provide the parameters with both of

them, such as the temperature and the dwell time.

Please provide your actual process. If the standard process we provide cant cover your actual process, please add

the related steps both in English and Chinese. ;

,()


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Chapter IV COMMON TEST ITEMS

4.1 Thermal Shock Test

4.1.1 Simulate conditions at which solder is applied to PWB during component mounting operation.

4.1.2 Conditioned at 121oC for 1.5 hours, then placing samples in oven at thermal shock temperature and time specified,

e.g. 260oC for 10sec.

121 1.5 260

10

4.1.3 Requirement: no wrinkling, blistering or loosening of any conductors or any delamination of base material.

,

4.2 Plating Adhesion Test

4.2.1 To test the application of conductor plating

4.2.2 Application of pressure sensitive tape onto unaged sample with conductor pattern, not subjected to thermal shock.

4.2.3 Requirement: no plating or conductors attached to the tape.

.

50.8-

82.6- 305 mm/min

90

Board & PatternSteel


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4.3 Bond Strength and Delamination Test

4.3.1 Force required to pull conductor from base material for a certain distance divided by the width of the conductor.

.

4.3.2 Bond Strength and Delamination Process

10- and 56-Day Oven Conditioning Temperature Calculation:10 56

10-Day (240 hours): Oven Temperature = 1.076 * (MOT + 288) 273

10240 1.076 * ( + 288) 273

56-Day (1344 hours): Oven Temperature = 1.02 * (MOT + 288) 273

561344 1.02 * (+ 288) 273

6.4 6.46.4

6.4

6.4 6.4

85-9085-90 85-90

Pull 1 Pull 3Pull 2

121C for

1.5 hours

PlatingAdhesion

&Thermal

shock

10 Day

conditioning

AsReceivedResults

10-DayAgingResults

Check fordelamination

and blistering

Check foracceptable bondstrength results

56 Dayconditioning

56-DayAging

Results Micro

sectioning

Check formicrosectioning

result

As received

testing


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4.3.3 Requirement: fullfill either (1) or (2):

12

(1) After 10-Day Oven Conditioning, 10 :

No delamination and blistering, ,

Bond Strength > 0.35 N/mm. 0.35N/mm

(2) After 56-Day Oven Conditioning, 56 :

No delamination and blistering, ,

Bond Strength > 0.175 N/mm, 0.175N/mm

4.4 94 V Flammability Test

4.4.1 Specimens are to be subjected to the thermal shock conditions.

4.4.2 Test Method is according to Section 8 in UL 94.

UL94 8

4.4.3 Flammability classification to be assigned to a printed-wiring board may be V-0, V-1, V-2. For details, please refer

to Standard UL 94 Table 8.1.

V-0, V-1, V-2 HB

4.4.4 When solder-resist is to be used in production, an additional set of specimens is to be provided, containing theapplied coatings. (21.2.1, UL 796).


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4.5 Conductive Paste Adhesion Test

4.5.1 Test for paste-type conductors employed on PWB, such as carbon paste, silver paste, or other conductive materials.

4.5.2 Conductive Paste applied on what surface?

?

Bare laminate, copper, solder resist or other surface.

4.5.3 Provide a cross sectional diagram with conductive paste and any undercoats, overcoats, base materials, solder resist,

conductors, etc, for determining the sample requirement.

,,

4.5.4 Requirement: There shall be no evidence of the conductor pattern being removed after testing.

46 Silver Migration Test

4.6.1 Test Process

4.6.2 Requirements:

a). No signs of silver migration are detected

b). Dielectric breakdown does not occur

Thermal shock Thermal Cycling

Plating

Adhesion test

ConductivePasteAdhesion

Test Results

SilverMigration

Test

Results

Measureminimum

spacingbetweensilverconductors

Dielectricvoltage

withstand testof 1.6kV/mmof minimum

spacing

Placed in humiditychamber held at 35 2C at 87.5 2.5%relative humidity, andenergized at therequested voltage

rating for 1344 hours

Kept at 23C 2C and50 %relativehumidity for48 hours

Check for

migration of silver

Check for migration

of silver

Second

dielectric voltagewithstand test as

described before


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Chapter V SAMPLE PREPARATION

5.1 SAMPLE PREPARATION - Prepare samples by subjecting them to ALL perations of the specified process.

Include all etching, baking and curing steps.

Expose the samples to all maximum times, temperatures and pressures.

Subject samples to the maximum number of cycles specified in any step.

5.2 BOND STRENGTH/DELAMINATION SAMPLES (Required 10 PCS) - Make certain the conductor pattern

which you use to build the samples reflect your rating requirements. These include:/ ( 10)

Minimum external copper thickness

Minimum conductor widths

Maximum unpierced diameter

Minimum thickness of laminate

Maximum internal copper thickness (if required)

Plated through-holes (if required)

Plated contact fingers (if required)

5.2.1 We will assign pattern limits based on actual measurements of the test samples.

5.2.2 The attachment contains illustrate typical test patterns.

5.2.3 The test pattern should appear on both sides of the sample, one s ide being the mirror image of the other. If youdesire Recognition for single -sided printed wiring boards only, the test pattern need only appear on one side of the

sample.

5.2.4 If the maximum unpierced diameter won't fit on the test pattern, please provide a separate set of samples. You may

etch these into either a circle or a square.

T2

5.2.5 Do NOT construct samples with solder resist on top of the conductor pattern.

5.2.6 COPPER THICKNESS - If you plan to buy copper clad laminate with a minimum copper thickness of less than 34

microns (1 -oz./square foot), you should plate your samples to 34 microns for testing purposes.

34 34

5.2.7 In production, if you plan to plate copper to more than 102 microns thick (3-oz./square foot), please provide an extra

set of samples built up to your maximum copper thickness.

102

5.2.8 Bond Strength & Delamination Test Sample Pattern


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Typical test pattern

A Minimum width conductor of configuration specified by the fabricator. See note e.

PWB e

B 1.6 mm (1/16 inch) wide conductor of configuration specified by the fabricator. See note e.PWB 1.6mm e

B1 (Not Shown) one or more potential widths may be included between A and B. See note e.

A B e C 9.5 mm (3/8 inch) diameter unpierced circular conductor

a.

9.5mm3/8inch a

D 12.7 mm (1/2 inch) diameter unpierced circular conductora.

12.7mm(1/2inch) a E Maximum diameter unpierced circular conductor specified by fabricator.

PCB

F Edge conductor. Shall be within 0.4 mm (1/64 inch) of the board edge, but not sheared at the edge. See note a and e.

0.4mm (1/64 inch) ae

G Plated- through holes.a

See note b. ab

H Plated contactsa, of minimum width. See notes b and c.

a bc

I Three contactsa, of maximum width. See notes b and c.

abc

a Optional, but must be on samples if acceptance of this type of construction is desired.

b Items E, G, H, and I may be provided on separate samples.

E,G,H I

c Plated contacts are required only if the plating is different from the conductor.


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d Test Pattern Artwork is available from the IPC, Order Department, 2215 Sanders Rd., Northbrook, Illinois, 60062.

IPC2215 Sanders Rd., Northbrook, Illinois, 60062

e Conductor patterns are required on the internal layers of multilayer samples. Internal conductor widths are to vary as

needed for the metal weights and thickness employed but shall not be narrower than the external conductor width.

Delamination Test Pattern

5.3 Construction of Samples for the 94V Flammability Test (Required 20 PCS)

94V- ( 20 )

5.3.1 Prepare the flammability samples by subjecting double sided laminate (unless you always use single- sided

laminate) to all steps of your manufacturing process. Remove all of the conductive material during etching. There

should be no holes in the specimens and the edges should not be frayed.

5.3.2 Note that the minimum thickness cannot be less than the minimum Recognized thickness of the base laminate.

Also note in certain instances, UL assigns minimum thicknesses based on standard tolerances. See Section 5.5 for

the minimum thickness values.

UL5.5

5.3.3 For multilayer flame specimens, remove all conductive material from both the internal and the external surfaces of

the samples during etching.

,

A Plated through holes.a

a

B Maximum unpierced circular conductorspecified by fabricator.

PWB

a

Optional, but must be on samples ifacceptance of this type of construction isdesired.

MaximumConductorDiameter

+ 1 inch

Maximum Conductor

Diameter

+ 1 inch

B

A


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NOTES:(a) Length: Samples should measure 125 5 mm (5.0 0.2 in.) in

length.

: 125 5 mm (5.0 0.2 in.)

(b) Width: Samples should measure 13.0 0.5 mm (0.5 0.02 in.) in

width.

: 13.0 0.5 mm (0.5 0.02 in.)

(c) Corners: The radius on the corners should be 1.3 mm (0.05 in.) or

less.

1.3mm

(d) Thickness: Samples should be of the minimum thickness to be

Recognized, and/or as specified in the samp le requirements.

W(b)

L(a)

(c)

T(d)


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25

5.4 Silver Migration Test Sample

Required 5 PCS

( 5)

5.4.1 The samples are to be wired to permit adjacent conductors representing minimum spacing.

5.4.2 A is the minimum spacing anticipated for a given voltage (1.6kV/mm of minimum spacing to a maximum of1000V).

A 1.6 1000

5.4.3 B and C are secondary spacings to be put on the test sample in the event the minimum spacing fails. Spacing B

is greater than A . Spacing C is greater thanB.

B CB CB A , C B

5.4.4 Minimum and secondary spacings are to be determined by the fabricator.

5.4.5 Spacing D is 0.3 mm. D 0.3

5.4.6 Traces shall be 0.3 mm wide. 0.3

5.4.7 The minimum board thickness shall be used.


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5.4.8 If permanent coating is used to retard silver migration, a set of samples incorporating each different coating shall be

submitted. Uncoated samples represent coated samples.

5.4.9 If the PWB Type is double sided, samples are to be double -sided.

5.4.10 Information required: minimum spacing between silver conductors and maximum voltage rating to be assigned.

5.5 Thickness range for all samples

Laminate minimum thickness

mm In

Thickness Range

mm In

Less than 0.020 Less than 0.0007 +/- 0.03 +/- 0.0001

0.02-0.074 0.0007-0.003 +/- 0.03 +/- 0.0001

0.075-0.099 0.003-0.004 +/- 0.07 +/- 0.0003

0.10-0.19 0.004-0.007 +/- 0.02 +/-0.0008

0.20-0.37 0.008-0.014 +/-0.03 +/-0.0012

0.38-0.62 0.015-0.024 +/-0.05 +/-0.019

0.63-1.59 0.025-0.061 +/-0.08 +/-0.0031

1.60-2.54 0.062-0.100 +/-0.10 +/-0.004

Greater than 2.55 Greater than 0.100 +/- 0.13 +/-0.005


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Appendix I Attachment

I

6.1 Good samples for a common request


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6.2 Detailed Description of Samples

6.2.1 Good Samples for B/D Test B/D

6.2.2 Wrong Samples for B/D B/D

1. There is no solder resist on

sample.

2. Exact surface treatment

according to process on the

conductors.

3. Size: 100 * 50mm.

100*50mm4. There are minimum conductor,

minimum edge conductor,

MAD.

1 If the MAD is too big, cantbe involved in above sample,

this one is needed.

2 If there is PTH step in

process, there must be PTH

on this sample.

PTH


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6.2.3 Good Samples for 94V Flame Test

Reason: There should be nosolder resist on B/D samples

B/D

1 Usually 2 sets samples for

94V Test, one is uncoatedand the other is coated with

solder resist.

2

2 Copper on both of these 2sets samples should beetched off, inner layer and

outer layer.

3 Size of samples is 125 (+/-

5)mm * 13(+/-0.5)mm. 125 (+/-5)mm *

13(+/-0.5)mm

pwb handbook[1]

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