Electronics Forum | Fri Feb 28 09:08:03 EST 2003 | davef
Without drilling through the numbers, they're probably correct. Recognize that standard warp / twist specs [IPC-A-610 1.5% for PTH only and 0.75% for SMT] are not going to make it on tech boards. You need to define specific requirements. This warp
Electronics Forum | Fri Aug 22 23:17:22 EDT 2003 | Hoss
Mike, Any chance these parts have been sitting around esposed to your factory's ambient conditions, not in a vacuum sealed bag or dry box? If they haven't, you may have parts with a high moisture content which could cause "potato chipping" you desc
Electronics Forum | Mon Aug 25 00:31:53 EDT 2003 | Dennis O'Donnelll
It could be moisture in the BGA. You should always bake the BGA before installation of course. But most likely you are usingf too much heat or too fast of a ramp speed. Make sure your top heater temp is below 230C. Set top heater to 220C, then adj
Electronics Forum | Tue Aug 26 08:59:27 EDT 2003 | fmonette
For more information on moisture-induced BGA warpage, I suggest you read the following paper that was recently presented at ECTC : "Impact of Ingressed Moisture and High Temperature Warpage Behavior on the Robust Assembly Capability for Large Body
Electronics Forum | Sat Feb 14 12:25:37 EST 2004 | I ramos
I populate several thin panels (0.032")using a > Samsung S-2000 P-N-P machine. With panel sizes > of 8" by 10", it is very difficult to clamp the > panels into the machine with deflection and > bowing. Also, the Samsung makes it very difficult
Electronics Forum | Thu Feb 19 18:07:57 EST 2004 | davef
We're inclined to buy Russ's stuff about peel from the wave. Look here, but shield your eyes first: [ http://www.thepdfshop.co.uk/ppm/defects/Wave/asp/50.asp ] [A respectful bow to BW for the pix] Could you tell us more about: * Board direction thro
Electronics Forum | Fri Apr 08 05:10:10 EDT 2005 | siverts
What is Your customers requirements? Is the PCBA mounted with front/back connectors? Will the PCBA be mounded in a rack and connected to opposite connectors on the other side? In this case, if the warpage is more than approx 1-1.5 % You will then n
Electronics Forum | Sun Apr 10 06:27:50 EDT 2005 | WarpSpeed
1.) First of all: What is Your customers requirements??? 2.) If the customer or You don't have a specification; I will strongly recommend that you follow the "IPC-IPC-TM-650 Method 2.4.22 Bow & Twist" that [DaveF] suggested. 3.) If You have "critic
Electronics Forum | Mon Oct 03 21:15:16 EDT 2005 | adlsmt
Its a single board, one up. 4 layer, pretty simple, no large copper pours. We get these consigned from our customer so I cant work that end of it but wanted to make sure to cover everything I can. The oven it runs in was just checked out by the facto
Electronics Forum | Mon Oct 03 22:12:53 EDT 2005 | davef
When we see warp and twist, we usually jump the fabricator for: * MLB construction (not homogeneous or unbalanced - too resin rich or poor) * Supplier process capabilities (lamination cycles) * Material selection (usually cheap and dirty), etc. War