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Courtyard Excess for TH not applied proportional

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jameshead View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jameshead Quote  Post ReplyReply Direct Link To This Post Topic: Courtyard Excess for TH not applied proportional
    Posted: 17 Sep 2012 at 3:15am
Settings are as program installed and not changed, i.e.

Setup and Fabrication Level is set to Proportional.

Terminals
    Throughhole
           Lead Widith <= 0.4 mm
           Lead Width > 0.4 mm

In both cases, User and Default Courtyard Excess is equal to 0.25 however no courtyard excess is applied to a axial resistor I tested and courtyard matches 3D body outline.

Withouth changing the "user" setting, i.e. as program is installed with all default .dat files:

If Setup > Fabrication Level is set to Level A then:

Terminals
    Throughhole
           Lead Widith <= 0.4 mm        User = 0.25 and Default = 0.50 
           Lead Width > 0.4 mm           User = 0.25 and Default = 0.50

(should user here, above, default to 0.5 to begin with before the user alters it?)

If Setup > Fabrication Level is set to Level B then:

Terminals
    Throughhole
           Lead Widith <= 0.4 mm        User = 0.25 and Default = 0.25
           Lead Width > 0.4 mm           User = 0.25 and Default = 0.25

If Setup > Fabrication Level is set to Level C then:

Terminals
    Throughhole
           Lead Widith <= 0.4 mm        User = 0.25 and Default = 0.25
           Lead Width > 0.4 mm           User = 0.25 and Default = 0.25

(should this be 0.1 mm or has IPC-7251 changed for new revision? Tom's presentation shows SMT courtyards but not through hole specifically)

I would expect Proportional to have a courtyard excess of some value and the "proportional" only to apply to the pad size.  Personally I don't use Proportional but always create A and B levels.


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Tom H View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Tom H Quote  Post ReplyReply Direct Link To This Post Posted: 17 Sep 2012 at 7:46am
Here are the default rules -
 
Goal

Courtyard Excess

Courtyard Round

Hole Over Lead

Min Annular Ring

Min Fab Allowance

Thermal ID Over Hole

Thermal OD Over ID

Spoke Width Pct

Lead  <= 0.40

Most

0.5

0.02

0.2

0.05

0.55

0.55

0.4

75

Nominal

0.25

0.02

0.15

0.05

0.45

0.35

0.25

75

Proportional

0.25

0.02

0.15

0.05

Calculated

Calculated

Calculated

75

User

0.25

0.02

0.15

0.05

0.45

0.35

0.25

75

Least

0.12

0.02

0.1

0.05

0.35

0.3

0.2

75

Lead > 0.40

Most

0.5

0.02

0.25

0.05

0.6

0.6

0.4

75

Nominal

0.25

0.02

0.2

0.05

0.5

0.4

0.3

75

Proportional

0.25

0.02

0.2

0.05

Calculated

Calculated

Calculated

75

User

0.25

0.02

0.2

0.05

0.5

0.4

0.3

75

Least

0.12

0.02

0.15

0.05

0.4

0.3

0.2

75

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