I stand corrected. Peer is right, a side fillet is also required. A toe fillet is not. -----Original Message----- From: P. Langeveld [mailto:[log in to unmask]] Sent: Friday, August 10, 2007 6:10 AM To: TechNet E-Mail Forum; Stadem, Richard D. Subject: Re: [TN] Minimum toe fillet for SOT23-3 land pattern In addition to the heel fillet, also a meniscus untill at least half lead thickness is required at the side of the lead feet as far as it has a protuding width of solder land underneath. If there is no protruding solder land, it is difficult to see if the full length of the feet is wetted. As a rule, the total leadframe must be wettable but, the tip of the toe is cut off after moulding. It has a clean surface that most of the time will be wetted, but it has no wetting requirement. Peer Langeveld Consultant Soft Soldering Processes The Netherlands 2007/8/9, Stadem, Richard D. <[log in to unmask]>: > The requirement is for a heel fillet only. Side and to fillets are > formed to exposed basis metals. While nice to have, they are not > required. Heel fillets are required and the specs are listed in > IPC-A-610D and J-STD-001D for Class 1, 2 and 3. The focus is on > aquiring a good heel fillet, as that is the part of the solder joint > that is formed with the finished surface of the lead. Side fillets and > toe fillets are suspect, at best, as the solder is forming an > intermetallic with oxidized basis metal. > > -----Original Message----- > From: TechNet [mailto:[log in to unmask]] On Behalf Of James Verrette > Sent: Thursday, August 09, 2007 11:54 AM > To: [log in to unmask] > Subject: [TN] Minimum toe fillet for SOT23-3 land pattern > > What should be the goal toe fillet for an IPC 7351 land pattern with > density level C for a SOT 23 - 3 pin package? (least protrusion, > highest density) > > > > > > Jim Verrette > > Electrical Engineer > > > > > > > --------------------------------------------------- > Technet Mail List provided as a service by IPC using LISTSERV 15.0 To > unsubscribe, send a message to [log in to unmask] with following text in > the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt > or > (re-start) delivery of Technet send e-mail to [log in to unmask]: SET > Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the > posts: send e-mail to [log in to unmask]: SET Technet Digest Search the > archives of previous posts at: http://listserv.ipc.org/archives Please > visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 > for additional information, or contact Keach Sasamori at > [log in to unmask] or 847-615-7100 ext.2815 > ----------------------------------------------------- > > --------------------------------------------------- > Technet Mail List provided as a service by IPC using LISTSERV 15.0 To > unsubscribe, send a message to [log in to unmask] with following text in > the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt > or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET > Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the > posts: send e-mail to [log in to unmask]: SET Technet Digest Search the > archives of previous posts at: http://listserv.ipc.org/archives Please > visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 > for additional information, or contact Keach Sasamori at > [log in to unmask] or 847-615-7100 ext.2815 > ----------------------------------------------------- > --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------