Electronics Forum | Wed Aug 19 08:00:55 EDT 1998 | Earl Moon
| Hi there, | I'm actually facing a lot of trouble with PCB's presenting up to 3mm of bow /twist at reception i.e. before assembly. The PCB size is 220 by 230mm. The boards are to be assembeled SMD double sides with 05.mm pitch on both sides. In orde
Electronics Forum | Thu Nov 17 03:34:51 EST 2005 | cangly
Hi, We have a board with over 100 chips (mixed size) and some long Connector DIP through out Wave solder with many issues of no solder and solder bridge, (using clean flux with bubble fluxer and Kester solder bar). Currently we tried to reduce the de
Electronics Forum | Thu Nov 17 21:46:48 EST 2005 | C. Kolokoy
With DIP type components, a sub-par fluxing method (foaming a no-clean), and a chip wave where one is not needed are formulas for bridging and insufficient wetting. If you have SMD's on the wave solder side of the board greater than 0603, and no SOT
Electronics Forum | Tue Sep 30 09:21:08 EDT 2008 | eedlund
Anyone using a No-clean solder paste on a pcb with a 100 Mbps Ethernet chip? Will the residue cause any signal degradation? Any issues with a no-clean solder paste and 1000 Mbps Gigabit Ethernet? Device: National Semiconductor DP83848 10/100 Mb
Electronics Forum | Thu Nov 17 20:51:16 EST 2005 | cangly
Morning Mike, We use Pb63/Sn37, Alpha Metal alloy. Solder pot is at 250 C. The profile of board after Preheat about 100 C, Lambda Wave about 220C (use both Lambda and Chip wave), DWell time 2.1s ~ 3s. Conveyor speed 1.5 in/min. We run by bare board a
Electronics Forum | Tue Mar 23 23:17:12 EDT 2021 | llawrence
Hello everyone, I work for a company that, up until now, has done everything using through-hole components. This has been fine for years, but we have been pushed into the world of surface mount manufacturing by a new product that is far cheaper and
Electronics Forum | Wed Jul 09 19:05:06 EDT 2003 | randywomack
LOZ. Under-cured or out-of-spec(sloppily) applied resist is realistic. What other physics: Shiny resist surface is more prone to balls then matte finish. How about an operator eating fish & chips before handling the boards. Don't laugh... ... saw th
Electronics Forum | Wed Mar 10 13:53:13 EST 1999 | Vincent Vega
| We will wave solder a board with SOIC14 and SOIC16 parts on the bottom. It has been difficult to find any specific wave solder process recommendations from manufacturers of the SOICs. The pad geometry utilizes theiving pads on both sides to reduce
Electronics Forum | Tue Sep 07 09:11:33 EDT 1999 | Dave F
| We've noticed that there are many different recommendations for pad sizes for various SMT parts. This seems to vary wildly from manufacturer to manufacturer for the same case sizes. Is there any standards that can used used to specify these sizes
Electronics Forum | Tue Apr 25 22:59:59 EDT 2000 | armin
If I were you, I would divide my boards into categories...and I'll categorize them by their components e.g. Bds with BGA, with QFP, Bds. with plain chip components...and so on...this is to create a recipe for each components with QFP's, BGA's etc...t
