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- SCMOSLib changes from V1.00 to V1.01
-
- -- The TDB files in the version 1.00 release contained objects which L-Edit
- considers "illegal." L-Edit PC simply ignores these objects, but L-Edit
- Macintosh will not load a file containing such objects. Version 1.01 files
- can be read by both PC and Macintosh versions of L-Edit.
-
-
-
- SCMOSLib changes from V1.01 to V2.00
-
- -- The pad cell "BareIOPad" has been added to the pad sets. This cell may be
- used as an unbuffered analog I/O pad or as a low-impedance I/O pad for
- heavily-loaded signals (such as clocks).
-
- -- The output pad cell "OPad" in the file SCN16U contained fatal errors.
- During editing and re-sizing of this cell for the version 1.00 release,
- geometry from another cell was inadvertently "pasted" on top of this cell.
- This error also existed in the version 1.01 release, but has been corrected
- as of version 2.00.
-
- -- Some DRC rule changes have been implemented: two new two design rules have
- been added, one has been deleted, one has been changed, and cosmetic
- changes have been made to most of the remaining.
-
- The first new rule is a 2 lambda select-to-select spacing rule. This rule
- is for lithographic reasons only. A 1 lambda wide sliver on the mask could
- break off and end up elsewhere on the mask.
-
- The second new rule is a 3 lambda transistor-to-select rule. This rule
- serves to keep well and substrate contacts far enough from a transistor so
- as not to affect the transistor's operation.
-
- The deleted rule is the select-to-active-in-well rule. This rule was
- intended to catch errors with well contacts but had the side effect of
- complaining about other legal structures.
-
- The minimum select width has been changed from 7 to 4 lambda. The select
- forming a well contact is allowed to be only 4 lambda wide.
-
- -- A variety of problems with the previous release have been corrected. Some
- of these problems were cosmetic only, some were potential problems only
- with the automatic place and route feature in L-Edit, and there were a few
- potentially fatal bugs.
-
- If you have not used SCMOSLib yet to make a chip, simply delete all copies
- of the previous release and use the latest release for your future work.
- If you have already created chips using cells from the previous library,
- read on.
-
- We were able to include fixes for all the known problems without increasing
- the size of any of the cells. Thus, when you update your design, you will
- not have to manually rework the positions of the cells. In most cases, we
- were able to also maintain the same port locations so that your wiring to
- the cells can remain the same. In three cells (AOI22, DFFC and DFFPC) we
- changed the port locations in minor ways so routing to instances of these
- cells will have to be reworked manually. In addition, two cells (Buf4 and
- BufI4) have changes to them which might create a design rule violation if
- they were wired to from the side, rather than the top or bottom. If you
- have used any of these five cells, please examine the wiring to them.
-
- If you require more detailed information concerning the changes made for
- this release or the errors in the previous release, please contact us.
-
-
- SCMOSLib changes from V2.00 to V2.01
-
- -- Some ports with no names have been deleted. These ports would not have
- affected actual fabrication of a design, but some CIF readers might
- complain about them. The affected cells and files are as follows:
-
- scn16u.tdb: cell OPad
- scp20u.tdb: cell CornerPad
- scp30u.tdb: cells Bar1, Bar3, Bar6, Bar7, Bar8 and CornerPad
-
- -- Known error in this release! The cell Nor2C has an occurrence of active
- extending over the select boundary. This problem will cause the gate to
- fail. To correct it, simply extend the select down over the active.
-
-
- SCMOSLib changes from V2.01 to V3.00
-
- -- The position of the "Cross" ports in many of the cells caused L-Edit's
- Standard Cell Core Router to create design rule violations during routing.
- We have repositioned many of these "Cross" ports, and on occasion moved the
- Metal2 under the port as well. These changes affect many cells in all
- libraries.
-
- -- The position of the ports in the cell Inv2 often caused L-Edit's Standard
- Cell Core Router to create design rule violations during routing. The
- ports in this cell have been repositioned, and the port has been widened
- by 1 lambda to make routing easier. This change affects the cell "Inv2" in
- all libraries.
-
- -- The cell "DFFP" contained a fatal layout error. There was a missing patch
- of Metal1 in the lower right corner of the cell, connecting a transistor to
- the the Q output. This flaw was in the "DFFP" cell in all libraries, and
- has been corrected.
-
- -- "Mirror" ports have been added to the pad cells in all libraries. These
- ports give L-Edit's Padframe Generator module necessary information about
- how to mirror the pads for automatic generation of a padframe. Refer to
- the Padframe Generation section in the L-Edit manual for more information
- regarding the Mirror Port.
-
- -- A bit of cleanup has been performed on various pad cells in all files.
- Some overlapping Poly and Well segments have been trimmed. These changes
- are cosmetic only.
-
- -- The "VddPad" and "GndPad" cells have been modified to prevent routing to
- the pad cell in Metal2.
-
- -- The "Vdd" and "Gnd" ports on the left and right sides of the pad cells in
- all libraries have been changed to be consistent. This change affects
- many pad cells in all libraries. No layout was changed.
-
- -- Some pad cells in the SCN12u library contained occurrences of Active too
- close to the bonding area. This was a design rule violation which could
- potentially cause a problem, if the bonding wire was not attached to the
- pad accurately. These occurrences has been corrected.
-
- -- The cell "CornerPad" was designed so that if another pad cell (other than
- a "CornerBar" cell) was placed directly abutting it, a power-to-ground
- short would take place. The "CornerPad" cells in all libraries have been
- modified to correct this potential problem.
-
- -- The pad cells "BPadZH", "IPadC", and "OPad" contained violations of the
- Metal1 to Metal1 Spacing, Metal2 to Metal2 Spacing, and Active Surrounding
- ActiveContact design rules. These violations were not fatal, but have been
- corrected in all libraries.
-
- -- Miscellaneous non-fatal design rule errors have been corrected in many pad
- cells in all libraries.
-
- -- The pad cell BareIOPad in the file SCN20u contained a fatal error
- involving the "Signal" wire. There was a 2 lambda gap in the cell's
- interior, causing this signal not to be connected. This has been
- corrected.
-
- -- A small port without a name was removed from the cell "CornerPad" in the
- file SCP20u.
-
- -- The cell "Nor2C" had an occurrence of active extending over the select
- boundary. This was a fatal error which has been corrected in all files.
-
-
- SCMOSLib changes from V3.00 to V3.01
-
- -- The Signal line on the pad cell BareIOPad in the library SCN12u was
- mistakenly placed on Metal1 instead of Metal2, which caused L-Edit's Place
- and Route to complain when using this pad. The Signal port on layer Metal1
- was removed, and a new Signal port on layer Metal2 was added. Also, Via
- and Metal2 patches were added to the cell to bring the line out on Metal2.
-
- -- An extra DataOut port on layer Metal1 in the pad cell IPadC in the library
- SCN12u has been removed. This was a cosmetic change only.
-
- -- The DataOut line on the pad cell OPad in the library SCN16u was mistakenly
- placed on Metal1 instead of Metal2, which caused L-Edit's Place and Route
- to complain when using this pad. The DataOut port was missing, and has now
- been added on layer Metal2. Also, Via and Metal2 patches were added to the
- cell to bring the line out on Metal2.
-
- -- The Signal port in the pad cell BareIOPad in the library SCP30u was
- erroneously shifted 9 lambda to the left. This would cause a fatal error
- if used with L-Edit's Place and Route, as a wire would not be connected
- properly to this cell.
-
- -- The Abut port in the pad cell OPad in the library SCN20u was erroneously
- shifted 8 lambda to the right, causing L-Edit's Place and Route to place
- the pad cell 8 lambda to the left of where it should be. This error was
- introduced in the release of version 3.00, and is fatal.
-
-
- If you find any errors or omissions, please call or write to us at the address
- below.
-
- L-Edit and SCMOSLib are trademarks of Tanner Research, Inc.
- Copyright (c) 1989-1990 Tanner Research, Inc. All rights reserved.
-
- Tanner Research, Inc.
- 444 North Altadena Drive
- Pasadena, CA 91107
-
- (818) 795-1696
- (818) 795-7937 Fax
-