IPC-TM-650 EN 2022 试验方法.pdf - 第758页

3.1 Coupon Design Rules Certain designs rules must be applied to achieve thermal uniformity. Electronic design files for coupon construction are available from the equipment supplier or printed board supplier. The resist…

IPC-2626-3-1

Figure 3-1 Method A Test Coupon

IPC-2626-3-2

Figure 3-2 Method B Test Coupon

IPC-TM-650

Number

2.6.26

Subject

DC Current Induced Thermal Cycling Test

Date

5/14

Revision

Page2of10

3.1 Coupon Design Rules Certain designs rules must be

applied to achieve thermal uniformity. Electronic design files

for coupon construction are available from the equipment

supplier or printed board supplier. The resistance values (volt-

age drops) for each coupon are monitored independently for

each electrical net in test, using a four wire measurement

technique.

The test coupon(s) is incorporated on the panel to monitor or

qualify design, materials, or processes of product and/or reli-

ability assurance.

4 Apparatus or Material At the time of publication of this

test method, 4.1 and 4.2 list the only known equipment

manufacturers of this test equipment. Equivalent test systems

may be used that operate on principles similar to those iden-

tified in Method A or B. IPC encourages their submission

along with relevant validation test data. This test method will

be revised as necessary to include these test systems as this

information becomes available.

Validation of this test method was performed with the equip-

ment listed in 4.1 and 4.2. Test conditions for the validation

are provided in 6.5. If alternate test equipment is used, valida-

tion in accordance with IPC-MDP-650 and 6.5 is recom-

mended.

4.1 Method A

4.1.1

This equipment is available from:

PWB Interconnect Solutions Inc. (Canada)

URL: www.pwbcorp.com

Equipment Type: IST

4.1.2 Two (2) four-pin, 2.54 mm [0.1 in] male connector

(ITW Pancon MFSS100-4-D or equivalent).

4.1.3 Sn60Pb40, Sn63Pb37, or lead free solder.

4.1.4 Solder flux.

4.1.5 Soldering iron.

4.2 Method B

4.2.1

This equipment is available from:

i3 Electronics (USA)

(formerly Endicott Interconnect Technologies)

URL: www.i3electronics.com

Equipment Type: CITC, CITC-TCR

4.2.2 4-wire multimeter, capable of measuring milliohms

4.2.3 Thermal imaging equipment – optional

5 Procedures

5.1 Sample Selection

5.1.1

Bench top measure the resistance of each net of the

coupon with a 4-wire multimeter. A net with an open cannot

be tested. A net with a short must be reworked to test the

coupon.

5.1.2 Coupon Selection Select coupons for evaluation

based upon the test required as described in 5.1.2.1 through

5.1.2.3.

5.1.2.1 Random Sampling A sample chosen without

regard to any characteristic of the individual coupons within a

population, within one or more lots.

5.1.2.2 Selective Sampling A sample chosen based on

the resistance measurements of the sense and power nets.

Testing may include high, midrange and low resistance mea-

surements.

5.1.2.3 Comparative Sampling A sample chosen based

on the resistance measurements of the sense and power

nets. Testing should include similar resistance measurements

for the populations being tested.

5.2 Method A Procedure

5.2.1 Single Sense Testing

Solder two four-pin male con-

nectors in the 1.02 mm [0.040 in] holes at the left and right

edges of the coupon (see Figure 3-1). A solder fillet must be

apparent on both sides of the coupon.

5.2.1.1 Dual Sense Testing (Optional) When Dual Sense

Testing is required, solder three four-pin male connectors in

the 1.02 mm [0.040 in] holes at the edges of the coupon (see

Figure 5-1). A solder fillet must be apparent on both sides of

the coupon.

NOTE: Dual Sense coupons may be tested using the Single

Sense Testing method.

IPC-TM-650

Number

2.6.26

Subject

DC Current Induced Thermal Cycling Test

Date

5/14

Revision

Page3of10

5.2.2 Position the coupons at each test head by attaching

male to female connectors.

5.2.3 Baseline Performance (Optional) Establish a per-

formance baseline by completing two Method A cycles and

then stop the test at the end of the cooling cycle.

5.2.4 Capacitance Test (Optional) If required, the capaci-

tance test shall be performed per IPC-TM-650, Method

2.5.35.

5.2.5 Assembly Precondition (Optional) Assembly pre-

conditioning is recommended to simulate the assembly envi-

ronment to which the printed boards are exposed (see 6.1).

5.2.6 Unless otherwise specified by the user, test all via

types and materials per the default test condition in accor-

dance with Table 5-1. For testing of samples containing

microvia structures, use the microvia test condition. For test-

ing of samples containing polyimide materials, use the polyim-

ide test condition.

5.2.7 Pre-Cycling Test Sequence The following para-

graphs detail the sequence for a single coupon, however this

sequence is done at all test heads simultaneously. The ambi-

ent resistance, resistance at test temperature, rejection resis-

tance, and current are calculated for each coupon and dis-

played on the PC monitor.

IPC-2626-5-1

Figure 5-1 Examples of Three Dual Sense IST Test Coupons (Top-Down View as shown at left and Isometric View as shown at right)

Table 5-1 Method A Typical Test Conditions

Test

Condition

Number

of Samples

Test

Temperatures

Failure

Threshold

(Resistance

Change)

Number

of Cycles

Data

Collection

Frequency

(Cycles)

Precycle

Time

Window

(seconds) Compensation

Default 6 150 °C 10% 250 25 3 Calculated

Polyimide 6 AABUS 10% 250 25 3 Calculated

Microvias

6 190 °C 10% 250 25 3 None

Polyimide

Microvias

6 AABUS 10% 250 25 5 None

Survivability

Testing

6 230 °C 10% 10 1 5 None

6 245 °C 10% 10 1 5 None

6 260 °C 10% 10 1 5 None

Note 1. For Dual Sense Testing, both the ‘‘Cycle Using’’ and the ‘‘Cycle Failing On’’ fields on the Method A test equipment shall be set to ‘both sense circuits.’

Note 2. Power on the microvia or heating trace net.

IPC-TM-650

Number

2.6.26

Subject

DC Current Induced Thermal Cycling Test

Date

5/14

Revision

Page4of10