Wendi,
The procurement documentation shall specify the thermal stress test method to be used to meet the requirement of 3.6.1. Selection shall be from those depicted in 3.6.1.1, 3.6.1.2 and 3.6.1.3. If not specified (see 5.1), the default shall be per Table 1-2.
During the selection process, the user should take into consideration the following when determining the appropriate thermal stress test method:
* Wave solder, selective solder, hand solder assembly processes (see 3.6.1.1)
* Conventional (eutectic) reflow processes (see 3.6.1.2)
* Lead-free reflow processes (see 3.6.1.3)
Table 1-2 Default Requirements
Category
Default Selection
Performance Class
Class 2
Material
Epoxy-Glass Laminate
Final Finish
Finish X
Minimum Starting Foil
1/2 oz. for all internal and external layers except Type 1 which shall start with 1 oz.
Copper Foil Type
Electrodeposited
Hole Diameter Tolerance
Plated, components
Plated, via only
Non-plated
(±) 100 µm [3,937 µin]
(+) 80 µm [3,150 µin], (-) no requirement, (may be totally or partially plugged)
(±) 80 µm [3,150 µin]
Conductor Width tolerance
Class 2 requirements per 3.5.1
Conductor Spacing tolerance
Class 2 requirements per 3.5.2
Dielectric Separation
90 µm [3,543 µin] minimum
Lateral Conductor Spacing
100 µm [3,937 µin] minimum
Marking Ink
Contrasting color, nonconductive
Solder Mask
Not applied, if not specified
Solder Mask, specified
Class T of IPC-SM-840 if class not specified
Solder Coating
Sn63/Pb37
Solderability Test
Category 2 of J-STD-003
Thermal Stress Test
IPC-TM-650, Method 2.6.8, Condition A
Test Voltage, Isolation Resistance
40 Volts
Qualification not specified
See IPC-6011
3.6.1 Thermal Stress Testing Test coupons or production PBs shall be thermally stressed. Per the applicable criteria listed in 1.3.3, one or more of the following Test Methods shall be required.
3.6.1.1 Thermal Stress Testing, Method 2.6.8 Test coupons or production PBs shall be thermally stressed in accordance with IPC-TM-650, Method 2.6.8, Test condition A.
3.6.1.2 Thermal Stress Testing, Method 2.6.27 (230 °C)Test coupons or production PBs shall be thermally stressed in accordance with IPC-TM-650, Method 2.6.27, 230° C Reflow Profile.
3.6.1.3 Thermal Stress Testing, Method 2.6.27 (260 °C)Test coupons or production PBs shall be thermally stressed in accordance with IPC-TM-650, Method 2.6.27, 260° C Reflow profile.
3.6.1.4 Deviations to Thermal Stress Testing Deviations to these requirements shall be AABUS.
Now you are at the Test Method. We have not changed the old one or its requirement for use. The default in the new one is 6 X 260°C, the last time I looked.
Dewey
-----Original Message-----
From: IPC-600-6012 [mailto:[log in to unmask]] On Behalf Of Wendi Boger
Sent: Thursday, April 30, 2009 7:02 AM
To: [log in to unmask]
Subject: [IPC-600-6012] Reflow testing
Everyone,
I have a quick question. When reviewing my notes from the meeting
I noted that the new reflow thermal stress frequency would be 1X reflow
= 1X solder float. I have a final draft of the 2.6.27 test method and
it shows 6x reflow cycles. Are we equating 1X solder float to 6X
reflow?
Is the test method released yet?
Wendi Boger
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