John,

Look at page two of the diode spec sheet for the maximum forward current derating curve (upper left corner).  The part may get really hot and the pads are used as a heat sink.  The forward current curve has the large pads as a requirement to achieve the maximum current on the derating chart.  Reduce the pad size and you would have reduced the maximum possible recommended current below what is shown on the derating curve.  I would talk to your Electronic Design Engineer before changing the pad size.  If the circuit current and temperature are never at the range where derating is necessary, you may get away with reducing the pad size.  Hope that helps.

Regards

Harold Hostetter

-----Original Message-----
From: DesignerCouncil [mailto:[log in to unmask]] On Behalf Of John Wheeler
Sent: Thursday, May 07, 2015 7:05 AM
To: [log in to unmask]
Subject: [DC] recommended DO-214AC landpattern

Question on a Fairchild recommended landpattern. Does anyone understand why this Fairchild is so different from what is typically recommend? What would you follow?


https://www.fairchildsemi.com/datasheets/ES/ES1J.pdf


Thanks,

John W

---------------------------------------------------------------------------------
DesignerCouncil Mail List provided as a free service by IPC using LISTSERV 16.0.
To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF DesignerCouncil.
To temporarily stop/(restart) delivery of DesignerCouncil send: SET DesignerCouncil NOMAIL/(MAIL) For additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
---------------------------------------------------------------------------------

______________________________________________________________________
This email has been scanned by the Symantec Email Security.cloud service.
For more information please contact helpdesk at x2960 or [log in to unmask] 
______________________________________________________________________




---------------------------------------------------------------------------------

DesignerCouncil Mail List provided as a free service by IPC using LISTSERV 16.0.

To unsubscribe, send a message to [log in to unmask] with following text in

the BODY (NOT the subject field): SIGNOFF DesignerCouncil.

To temporarily stop/(restart) delivery of DesignerCouncil send: SET DesignerCouncil NOMAIL/(MAIL)

For additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815

---------------------------------------------------------------------------------