The PCB Footprint Expert is a powerful CAD library development tool powered by our own proprietary CAD LEAP Technology (Libraries Enhanced with Automated Preferences). It is packed with very powerful advanced library management features that cuts foo
Electronics Forum | Thu Jan 08 14:33:50 EST 2004 | dwzeek
Toe fillets are not required per IPC. Toe fillets could be used as a process indicator, if you desire; I would not. Gull wing leads are typically cut off on the ends when manufactured; this exposes the non-plated material in the lead, typically coppe
Electronics Forum | Thu Mar 29 08:28:28 EDT 2012 | williamaxler
In the IPC-A-610E standard QFNs are classified as BTC (bottom termination components). Most QFNs do not have a solder-able surface on the outside of the part. Usually the lead that you can see on the outside is copper and classified is not solder-a
Technical Library | 2018-05-23 12:12:43.0
Driven by miniaturization, cost reduction and tighter requirements for electrical and thermal performance, the use of lead-frame based bottom-termination components (LF-BTC) as small-outline no-leads (SON), quad-flat no leads (QFN) packages etc., is increasing. However, a major distractor for the use of such packages in high-reliability applications has been the lack of a visible solder (toe) fillet on the edge surface of the pins: because the post-package assembly singulation process typically leaves bare copper leadframe at the singulation edge, which is not protected against oxidation and thus does not easily solder-wet, a solder fillet (toe fillet) does not generally develop.
The PCB Footprint Expert is a powerful CAD library development tool powered by our own proprietary CAD LEAP Technology (Libraries Enhanced with Automated Preferences). It is packed with very powerful advanced library management features that cuts foo
SMTnet Express, November 22, 2017, Subscribers: 31,034, Companies: 10,792, Users: 24,082 Factors Affecting the Adhesion of Thin Film Copper on Polyimide David Ciufo, Hsin-Yi Tsai and Michael J. Carmody; Intrinsiq Materials Inc. The use of copper
Heller Industries Inc. | https://hellerindustries.com/wp-content/uploads/2018/07/leadfree.pdf
Procured test board with bare copper pads protected with OSP. (Future testing to be run with HASL Lead Free Pads) ♦ Tested 2 pastes: ♦ 96.5% Sn/3.5% Ag with RMA flux melt point 221
