If we need to rework a QFN for insufficient solder/suspected non-wetting, then we pull the part off and add solder by hand with an iron. We visually inspect and rework the deposits, taking care to make sure the heights are even, then use paste flux and hot air to put the part back down. No, its not fun! Wayne Thayer >>> [log in to unmask] >>> The component is a TI package and the link you show is the type I'm referring to. The only difference is the part we are using has 10 pins with a large thermal pad in the middle. How are others inspecting QFN style components? How are others reworking QFN style components? Are you removing the QFN, or are you adding to the pin that may have insufficient solder? If you remove the component, how are you dealing with the fine pitch issue and getting new paste on the board or solder in general on the pads so that you can reflow the new component? We have boards that show the solder paste was insufficient (no solder at those unprotected lead frames at the sides) and we need to add solder, we are only visually inspecting with an AOI and manually. There are no guarantees that solder will flow to the bottom of the component by just adding to the outside toe area, so how are others handling this type of rework? Thanks, Jim West Engineering Manager Nexergy Inc. www.nexergy.com tel: (614) 351-6216 fax: (614) 324-1979 This email message and all attachments transmitted with it are intended solely for the use of the addressee(s) and may contain legally privileged, protected or confidential information. If you believe that you have received this message in error, please notify the sender immediately by email reply and please delete this message from your computer and destroy any copies. -------------------------------------------------------- -----Original Message----- From: David Greig [mailto:[log in to unmask]] Sent: Thursday, December 28, 2006 11:46 AM To: 'TechNet E-Mail Forum'; West, Jim Subject: RE: [TN] DRK package Jim Have a look at <http://focus.ti.com/lit/an/scba017d/scba017d.pdf> I'm guessing DRK is a TI package. QFN/DFN are normally plated whilst panelised, and then sawn or singulated. As a result they have unprotected lead frame material at the sides. A "toe fillet" is still useful to get heat into the joint during reflow, and most certainly so for rework or hand assembly (I have a love hate view on these depending on whether I'm my minds on electrical/thermal performance or my hands are on the hot air gun for prototypes!) Best Regards David Greig ______________________________ GigaDyne Ltd 5 Albany Business Centre Gardeners Street Dunfermline KY12 0RN United Kingdom t: +44 (0)1383 624 975 www.gigadyne.co.uk ______________________________ -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of West, Jim Sent: 28 December 2006 14:27 To: [log in to unmask] Subject: [TN] DRK package Hi, Looking for some help with the package shown within this email. The package virtually sits flush with the PCB, and the pads are directly under the body of the part. The pads are exposed on the side, but by a very small amount. I have a lot of questions regarding the processes from the beginning to the end, but wanted to see if anyone else runs this type of package and what your experiences have been like? Some questions would be stencil apertures design guideline, paste height, after reflow inspection method, and reworking. Best Regards, Jim West Engineering Manager Nexergy Inc. www.nexergy.com tel: (614) 351-6216 fax: (614) 324-1979 This email message and all attachments transmitted with it are intended solely for the use of the addressee(s) and may contain legally privileged, protected or confidential information. 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