AVX TurboCap Footprint

Message Topic Search Topic Options Post Reply Create New Topic Printable Version Translate Topic

What should the heel, toe and side solder joint dimensions
be? AVX Turbo Cap, J style leads, ST205C series High_CV SMPS capacitor. Link to
data sheet:

 http://www.avx.com/docs/Catalogs/turbocap.pdf

Author	Message Topic Search Topic Options Post Reply Create New Topic Printable Version Translate Topic
RLS2004 Members Profile Send Private Message Find Members Posts Add to Buddy List Advanced User Joined: 26 Jan 2012 Location: Seattle,WA Status: Offline Points: 51	Post Options Post Reply Quote RLS2004 Report Post Thanks(0) Quote Reply Topic: AVX TurboCap Footprint Posted: 27 Apr 2012 at 11:45am
	What should the heel, toe and side solder joint dimensions be? AVX Turbo Cap, J style leads, ST205C series High_CV SMPS capacitor. Link to data sheet: http://www.avx.com/docs/Catalogs/turbocap.pdf
	RLS2004



Tom H Members Profile Send Private Message Find Members Posts Add to Buddy List Admin Group Joined: 05 Jan 2012 Location: San Diego, CA Status: Offline Points: 5718	Post Options Post Reply Quote Tom H Report Post Thanks(1) Quote Reply Posted: 27 Apr 2012 at 12:12pm
	You need more than Toe, Heel & Side dimensions to calculate the Pad Size and Spacing. These 7 factors are used to calculate the optimum Land Size Component Body Tolerance – ± 4 Mil (0.1) thru ± 12 (0.3) Component Terminal Tolerance – ± 8 Mil (0.2) thru ± 20 Mil (0.5) Fabrication Tolerance – ± 2 Mil (0.05 mm) Placement Tolerance – ± 1 Mil (0.025 mm) Land Size Round-off – ± 1 Mil or (0.01 mm) Land Spacing Round-off – ± 1 Mil or (0.01mm) Solder Joint Goals for Toe, Heel and Side The new IPC-7351 Footprint Calculator will be available for Free download with a login or registration requirement on May 21 on the front page of the upcoming www.pcblibraries.com website. Also, the "J Style Leads" are really "Outward L Bend" - The new upcoming 2012 IPC Footprint Calculator is component lead based to handle every component family. But for the time being here is the info you asked for - Toe = 14 mils (0.35 mm) Heel = 14 mils (0.35 mm) Side = 2 mils (0.05 mm) If you use mils, round-off the pad size and pad center spacing in 1 mil increments.

RLS2004 Members Profile Send Private Message Find Members Posts Add to Buddy List Advanced User Joined: 26 Jan 2012 Location: Seattle,WA Status: Offline Points: 51	Post Options Post Reply Quote RLS2004 Report Post Thanks(0) Quote Reply Posted: 27 Apr 2012 at 12:56pm
	Hi Tom, Thanks for the reply. Did you note that the "J style leads" on this part bend UNDER the component. Looks similar to an SOIC but the leads bend under the part. Old IPC-SM-782 page 10 figure 3-2 shows a "C" bend style of lead that looks similar to this part. What 7351 component family would you recommend for this part?
	RLS2004

Tom H Members Profile Send Private Message Find Members Posts Add to Buddy List Admin Group Joined: 05 Jan 2012 Location: San Diego, CA Status: Offline Points: 5718	Post Options Post Reply Quote Tom H Report Post Thanks(0) Quote Reply Posted: 27 Apr 2012 at 1:33pm
	My mistake, but the same solder joint goals for Toe, Heel and Side apply. IPC-7351 uses "Component Families" to break down solder joints. The new IPC Footprint Calculator uses "Component Leads" instead. There are 150 different standard component families and unknown number of non-standard component families, but there are only 21 different Component Lead Styles. What do these Component Families have in common? Ceramic Flat Pack (CFP) Ceramic Quad Flat Pack (CQFP) Small Outline Diode (SOD) Small Outline Transistor (SOT23, SOT223, SOT343 & SOT143) Small Outline Package (SOP) Transistor Outline (TO or DPAK) They all have a Gull Wing lead form. So why apply the same rules to 9 different component families when it's better (more efficient) to apply rules to a single Lead Form. We still have component families in the Footprint Calculator, but the "Preference Rules" are much simpler when the rules are applied to the "Lead Form".