REGARDING [TN] Net list help
Here's what we do:
In general for intra-sheet connections we have no connections via dangling nets.
If you have a general rule that dictates intra-sheet signals on the left and right side of the sheet you can follow these guidelines:
Signal to a distant sheet should not traverse intervening sheets
Inter-sheet references for sheet inputs and outputs:
>Sheet inputs, only one reference to the signal source sheet
>Outputs, one reference for each load destination sheet
Overall we:
Sheets: Size D with standard borders
Hierarchy: Flat at PCB level. No hierarchies to the board schematic.
Process flow: Left-right, top-bottom, ascending sheet order
Reference designations:
Order: left-right, top-bottom, sheet-sheet
No renumbering, except by mutual agreement by EE and designer
Ref-Des Table on sheet 1; Last-used, Unused, Out-of-Sequence,Not-Installed
Signal inputs left edge of sheet, outputs right edge:
Exception for "columnized" circuitry
No intra-sheet connections via dangling nets
Signal to a distant sheet should not traverse intervening sheets
Inter-sheet references for sheet inputs and outputs:
Sheet inputs, only one reference to the signal source sheet
Outputs, one reference for each load destination sheet
Symbol placement on grid of 10 units (100 mils)
Net spacing 20 units minimum (200 mils)
Text:
Composed as "fixed" stroke font, mapped to Arial at scale 1.8
Size 10 units minimum preferred (110 mils actual character height)*
Pin numbers of discretes: 8 units (90 mils)*
Reference Designations 13 units (140 mils)*
Drawing Number: 25 units (275 mils)*
Schematic Title: 20 units (220 mils)*
Sheet numbering:
First sheet: "Sheet 1 of n"
Subsequent: "Sheet 2", Sheet 3", etc.
All sheets dated synchronously at last change for any sheet
Avoid extremes of low or high circuitry density
Signal naming:
Negation by suffixed slash (/)
Redundancy designator after any negation character - "XYZ/-A", "XYZ/-B"
Sheet 1 requirements:
No circuitry, no components
General notes
Table of Reference Designators
Table of revisions, upper right
Table of contents, circuit functional blocks versus sheet number (Optional)
* Text scaling: Actual character height is approximately 1.1 larger than the "size" setting when mapped to Arial and scaled at 1.8. (A WorkView "unit" is 10
mils.)
Also, we leave off 'zones' as this generally confuses the readibility of the schematic - since we generally have inputs on the left and outputs on the
right, it isn't necessary to use a zone to find the net you want.
Hope this helps.
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