This is NOT a firm answer, but just a guess.

Perhaps your TSOP 10x20 - 40 pin is a TSOP Type II.

The TSOPs in IPC-SM-782 are TSOP Type I. JEDEC has added a new TSOP outline called
TSOP Type II.

The IPC -SM-782 committee is looking at the outlines to develop new land patterns for
the Type II, but is currently focusing their efforts on publishing land patterns for
BGAs. When that is completed, we will finish the Type II land patterns.


Lisa Williams
IPC
2215 Sanders Road
Northbrook, IL  60062
URL:  www.ipc.org

>>> Walter Williams <[log in to unmask]> 06/01/98 02:44PM >>>
Greetings all

I have and Intel 28F008S5 flash I trying to create a land pattern
for. The data sheet does not give any part dimentiond but claims it
to be a TSOP 10x20. The 782 IPC book says that the pin spacing .3 mm.
But this has proven to be incorrect. Does any one have any insight as
to why the part mfg. and the IPC book differ?

There is some information that I left off. The Intel data sheet also
says it is a 40 pin package. A little over sight on my part.

TSOP 10x20 40 pin


*************************************************
Thanks
Walter L. Williams, Circuit Board Designer
I-O Corporation, SLC, Utah
Industry leader in IBM AS400 connectivity products
[log in to unmask]
Voice: 1-801-972-3558 ex 123
Alternate: 1-801-973-6767
*************************************************
Carpe Diem

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