Designing a VLSI layout is very strenuous and time consuming. Stick diagram is an intermediate step between the schematic and layout which shows the. Stick Diagrams. ▫ VLSI design aims to translate circuit concepts onto silicon. ▫ stick diagrams are a means of capturing topography and layer information using. To learn how to draw stick diagrams for a given MOS circuit. Outcome VLSI design aims to translate circuit concepts onto silicon. stick diagrams are a means of.
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Pad overlap of glass opening: Does not show exact placement, transistor sizes, wire lengths, wire widths, tub boundaries. Pull-Down Network The easy part!
VLSI_Design Rules,Layout And Stick Diagram Lecture04 |authorSTREAM
April 29, Digital Design Automation 47 Cell Connection Schemes External connection - wire cells together Abutment - design cells to connect when adjacent Reflection, mirroring - use to vlsi stick diagrams abutment possible Example: April 29, Digital Design Automation 48 Example: Sticks design of multiplexer: April 29, Digital Design Automation 55 Example: Exterior of Cell Example - Magic Layout: Performance vlsi stick diagrams how fast is the clock?
Absolute mask one layer for each mask Magic: Compare layout, schematic netlists Compare transistors, connections ignore parasitics Issue error if two netlists are not equivalent Important for large designs Automatic Layout Tools: Procedural specification of layout see book Fig.
April 29, Digital Design Automation 67 Layout design and analysis tools Layout editors are interactive tools. Manufacturing processes have inherent limitations in accuracy.
Design rules specify geometry of masks which will provide reasonable yields. Design rules are determined by experience.
April 29, Digital Design Automation 13 Manufacturing problems Photoresist shrinkage, tearing. Variations in material deposition.
Art of layout,Euler's path & stick diagram | VLSI System Design
Variations in oxide thickness. Variations across a wafer.
April 29, Digital Design Automation 14 Transistor problems Varaiations in threshold voltage: April 29, Digital Design Automation 17 Via problems Vlsi stick diagrams may not be cut all the way through.
Undesize via has too much resistance. Via may be too large and create short. Designed to support multiple vendors.
Drawing Stick Diagrams
Designed vlsi stick diagrams educational use. Here there will be only one conductor crossing the square Metal1 power or ground rail.
An N-Well Tap is inferred where the connection is from a power rail while a Substrate Tap is inferred where vlsi stick diagrams connection is from a ground rail.
Here the tap shares the same Active Area as the contact. A combined contact and tap is defined using a filled black square in place of the source contact filled black circle.