IPC-TM-650 EN 2022 试验方法--.pdf - 第766页

1 Scope and Purpose 1.1 Sco pe This method is intended to si mulate exposure to the thermal co nditions by convection ref low a ssembly. 1.2 Pur pose This method be used to replicate the thermodynamic effects by as sembl…

7. When the thermocouple/ thermometer measures 150 °C,

record the resistance of the Sense net with a 4-wire cable

and a bench top multi-meter.

8. For validation, compare the resistance readings of the

manual measurements in the oven and the test machine

for each coupon.

6.5.1.2 Test Temperature/Resistance Validation

1. Verify the equipment is calibrated and ready for use.

2. Load coupons into all test heads on the test machine.

3. Enter the test parameters shown in Table 6-3 (or equiva-

lent) into the test machine.

4. For Cycle 2, measure the resistance at 150 °C and at room

temperature on the test machine.

5. For validation, compare the resistance measurement at

150 °C between test machines and at room temperature

between test machines.

6.5.2 Method B

6.5.2.1 Temperature Coefficient of Resistance (TCR)

Validation

1. Label coupons and record 4-wire resistance with bench

top multi-meter.

2. Measure the temperature and resistance at the following

equilibrium temperatures: 23, 75, 125, 150, 175, 200, and

220 °C. Calculate TCR for test temperature 23-220 °C.

3. For validation, compare the measured TCR values

between test machines.

6.5.2.2 Test Temperature/Resistance Validation

1. Run 3 cycles for test temperature 23-220 °C using the

mean TCR measured in 6.5.2.1.

2. For Cycle 3, record the calculated temperature T(calc,

high) at end of high temperature dwell.

3. For validation, compare the T(calc, high) value between

test machines.

Maximum # Cycles 5

Data Recorded 1

Test Temperature 150 °C

% Rejection Sense Circuit 10%

% Rejection Power Circuit 10%

Precycle Time 5

Compensation Calculated

Number

2.6.26

Subject

DC Current Induced Thermal Cycling Test

Date

5/14

Revision

IPC-TM-650

Table

6-3

Temperature

Coefficient

Resistance

(TCR)

Validation

Parameters

Test

Parameter

Setting

Page

1 Scope and Purpose

1.1 Scope

This method is intended to simulate exposure to

the thermal conditions by convection reflow assembly.

1.2 Purpose

This method be used to replicate the

thermodynamic effects by assembly on the test specimen.

The use of this method is intended to simulate those effects

that are the result of soldering thermal excursions.

1.2.1

This method be used for qualification testing of

an applicable test specimen. The evaluation of acceptability

for qualification

be in accordance with the requirements

defined in 5.3.

1.2.2

This method may be used for lot acceptance. The

evaluation for lot acceptability should be in accordance with

the requirements defined in 5.3 or as agreed upon between

user and supplier (AABUS).

2 Applicable Documents

Terms and Definitions

Generic Standard on Printed Board Design

Acceptability of Printed Boards

Printed Board Handling and Storage Guidelines

Qualification and Performance Specification for

Rigid Printed Boards

Qualification and Performance Specification for

Flexible Printed Boards

Qualification and Performance Specification for

High Frequency (Microwave) Printed Boards

Guidelines for Microsection Preparation

User’s Guide for IPC-TM-650, Method 2.6.27

Test Methods Manual

2.1.1 Microsectioning – Microsectioning, Manual and Semi

or Automatic Method

3 Test Specimen

3.1 Design/Construction Criteria

3.1.1

The test specimen be the A/B, AB-R, and/or the

D coupon as designed in accordance with the requirements of

IPC-2221 Appendix A or B. Use of alternate specimens

be AABUS.

3.1.2

The test specimen(s) be constructed with holes

contained in the printed board it represents as follows:

a. A/B, A/B-R and D coupons

be constructed with

both the largest plated through-holes (PTHs) and the

smallest vias.

b. Propagated B and D coupons

be constructed with

the intended via structure. (Multiple B and D coupons are

used for designs with multiple structures.)

3.1.2.1

The test specimen(s) contain the representa-

tive ground and power planes of the printed board design.

3.1.2.2

The test specimen(s) contain the representa-

tive filled through vias, applicable blind and/or buried vias,

including microvias, of the printed board design.

3.1.3

The test specimen(s) allow for microsection

evaluation of all the applicable, representative PTHs and vias

defined in 3.1.2 after exposure to the conditions of this Test

Method.

Special tooling may be required for potting an entire

‘‘D’’ Coupon for microsection examination.

3.1.4

Deviations to the test specimen design/construction

or use of an alternate test specimen such as the printed board

or a section of the printed board

be AABUS.

4 Apparatus

4.1 Drying Oven

4.1.1

The oven be capable of maintaining a uniform

set temperature within the 105 to 125 °C [221 to 257 °F]

range.

1. Current and revised IPC Test Methods are available on the IPC Web site (www.ipc.org/test-methods.aspx).

3000 Lakeside Drive, Suite 105N

Bannockburn, IL 60015-1249

IPC-TM-650

TEST METHODS MANUAL

Number

2.6.27

Subject

Thermal Stress, Convection Reflow Assembly

Simulation

Date

2/2020

Revision

Originating Task Group

Thermal Stress Test Methodology Subcommittee

(D-32)

Association

Connecting

Electronics

Industries

shall

IPC-T-50

IPC-2221

IPC-A-600

IPC-1601

IPC-6012

IPC-6013

IPC-6018

IPC-9241

IPC-9631

IPC-TM-650

Note:

shall

Material

this

Test

Methods

Manual

was

voluntarily

established

Technical

Committees

PC.

This

material

advisory

only

and

use

adaptation

，

entirely

voluntary.

IPC

disclaims

all

liability

any

kind

the

use,

application,

adaptation

this

material.

Users

are

also

wholly

responsible

for

protecting

themselves

against

all

claims

liabilities

for

patent

infringement.

Equipment

referenced

for

the

convenience

the

user

and

does

not

imply

endorsement

IPC.

Page

4.2 Convection Reflow Oven or Simulator

4.2.1

The system used to simulate the thermodynamic

effects of assembly

be convection reflow.

4.2.1.1

The system have adequate environmental

controls to maintain the tolerance range and limits in accor-

dance with the reflow profile depicted in either Figure 5-1,

Figure 5-2 or Figure 5-3.

4.2.1.2

The system should accommodate verifiable calibra-

tion compliance and reflow profile generation. See note 6.1 for

additional considerations.

4.2.1.3

The test specimen be handled and stored in a

controlled environment to minimize moisture ingression. See

IPC-1601 for details on the proper handling and storage of

test specimens.

4.2.2

Deviations to the equipment requirements and

acceptability of the alternative methods

be AABUS.

4.3 Microscope

4.3.1

The magnification used for defect recognition must be

in agreement with the inspection requirements/capabilities

defined in the applicable performance specification (e.g., IPC-

6012, IPC-6013, IPC-6018, etc.) and IPC-A-600.

4.4 Resistance Measurements of IPC-2221 Appendix A,

D Coupons

4.4.1

When specified by performance specification or pro-

curement documentation, resistance measurements of the

IPC-2221B Appendix A, D coupons

be required.

4.4.2

The resistance measurement have enough pre-

cision to clearly determine the resistance percent change as

required by the user for the resistance level of each sample’s

nets.

4.4.3

The total system uncertainty from resistance, tem-

perature and time/cycle variations

be less than 10% of

the failure criteria required by the user. For example, if the

required failure criteria is 5% then the total system uncertainty

be no greater than 0.50%.

4.4.4

The resistance data consist of at least 1 reading

per sample net every second during the entire reflow cycle.

5 Procedure

5.1 Conditioning

5.1.1 The test specimen be conditioned by drying in an

oven to remove moisture for a minimum of six (6) hours at 105 to

125 °C [221 to 257 °F].

5.1.2

Test specimens that are thicker or more complex may

require longer baking times to achieve acceptable moisture

levels. Record the bake times and temperature if different than

those stated in 5.1.1. See IPC-1601 for additional guidance

on baking to achieve acceptable moisture levels. See note

6.2.

5.1.3

Deviations to the conditioning requirements in 5.1.1

such as when used for acceptance criteria and/or any

changes to the time and temperature

be AABUS. See

6.3.

5.2 Reflow Profile

5.2.1

Reflow the test specimen in accordance with Table

5-1 (default), Table 5-2 (low temperature profile) or Table 5-3.

5.2.2

The reflow profile be in accordance with either

Figure 5-1, Figure 5-2 or Figure 5-3. Figure 5-1 represents the

default reflow profile. Figure 5-2 represents the low tempera-

ture profile. Figure 5-3 represents a 245 °C reflow profile. The

times to t1, t2 and t3 may vary based on the mass of the

sample test specimen. To avoid over stressing of samples,

times should be shortened for low mass samples. Times

should be extended for high mass samples, such that the

zone (air) temperature

be more than 25 °C above

the target surface temperature at any point in the cycle.

The attachment of thermocouples to the sample test speci-

men

be such that the reflow profile is calibrated to the

surface temperature of the test specimen.

5.2.3

The test specimen be subjected to a minimum

of six (6) reflow cycles.

5.2.4

The cool down rate be in accordance with Table

5-1, Table 5-2 or Table 5-3, based on the reflow profile

selected in 5.2.1. The cool down is complete when the test

specimen reaches 45 °C. The test specimen

achieve a

thermal equilibrium of 45 °C or less prior to starting the next

reflow cycle. If the time it takes to achieve thermal equilibrium

cannot be determined, then a five (5) minute dwell between

reflow cycles

be required.

5.2.5

Deviations to the reflow profile or number of cycles

be AABUS.

Number

2.6.27

Subject

Thermal Stress, Convection Reflow Assembly Simulation

Date

2/2020

Revision

IPC-TM-650

shall

not

shall

Page