pcb英语

Common Query

I. Board thickness

1. Lay-up

2. Mismatch between the lay-up board thicknesses

3. Relax board thickness tolerance

II. Carbon ink

III. Cu thickness & Pad

1. Add Cu clearance for NPTH or consider 2nd-drill

2. Add dummy pattern

3. Copper close to board edge

4. Copper extending to unit edge

5. Delete NPTH pad

6. Distance between two pads less than 4mil

7. Isolated fiducial mark

8. No space to enlarge pads to ensure 2mil annual ring

9. Pad size is too small

10. PTH hole with elliptic pad

11. Relax Cu thickness on outer layer

12. Relax Cu thickness on outer layer

IV. DWG

1. Label in DWG is undefined

2. No DWG with dimension

3. Unit DWG size is small

V. General criteria

1. Common criteria

2. E/T stamp

3. Our logo

4. X-out

VI. Gold finger

1. Delete solder mask bridge between gold fingers

2. Relax tolerance for bevel size

3. Relax beveling angle or disregard the remaining thickness

4. Space between gold finger edge and outline is too narrow

5. Space between test pad and the top of gold finger is too narrow VII. Hole

1. Blind/buried hole

2. Breakaway hole is partially on copper plane

3. Change overlapped hole as slot

4. Drilling positional tolerance

5. Relax tolerance for NPTH

6. Relax tolerance for PTH

7. Repeated hole

8. Routing hole

9. Rectangular hole

VIII. Impedance

1. Calculated value trends to the limit

2. Match impedance

3. Reference plane

4. Which trace should be controlled

IX. Inner corner

Right angle

X. Outline dimension

1. Connection tab far away from unit edge

2. Mismatch between CAD/CAM data and DWG

3. Miss dimension

4. Narrow connection area between breakaway holes

5. No tooling hole

6. Relax tolerance for outline dimension

7. Uneven tolerance

8. Useless dimension

9. Add overshoot

XI. Packing

XII. Peelable solder mask

1. Peelable solder mask covered hole

2. Peelable solder mask plugged hole

3. Relax thickness for peelable solder mask

4. Without the detail dimension of peelable solder mask XIII. Silkscreen

1. Marking in hole or pad

2. Marking in large solder surface

3. Legend on step area

XIV. Slot

1. Relax tolerance for non-plated slot

2. Relax tolerance for plated slot

XV. Solder mask

1. Add S/M Bridge for SMT

2. Change S/M plugged hole to covered hole

3. Hole size is too large to plug

4. Hole size is too small to cover

5. Relax solder mask thickness

6. S/M cover gold finger

7. Solder mask material

8. Spacing is too narrow to add S/M Bridge

XVI. Solder thickness

Relax solder thickness

XVII. TAB

Without TAB on one row of units at the center XVIII. Tg

Tg value is not specified for High Tg material

XIX. Trace

1. Connection between Cu grounds is too thin

2. Exposed trace from solder mask opening

3. Relax etching tolerance

4. Self-spacing

5. Spacing between two traces is too narrow

XX. Transfer board

Sample approval

XXI. V-Cut

1. Discontinuous V-Cut

2. Relax V-Cut remain thickness tolerance

3. Relax V-Cut groove angle tolerance

4. V-Cut remain thickness is too weak

5. V-Cut run across BAT

XXII. Warpage

Relax warpage