1. Blog>
  2. PCB test items

PCB test items

by: Dec 13,2013 722 Views 0 Comments Posted in Engineering Technical

Circuit board board PCB test items

label: PCB test items,board,Circuit board

Substrates bad judgment

1 plate edge feather

Acceptance: board edge roughness, has not affected the match function.

Failed: board edge consecutive break burr, this will affect the matching feather and function.

2 board edge notch

Acceptance: board edge notched damage, but not intrusive to the nearest half or wire spacing 2.5mm (depending on the lesser).

Failure: the gap has more than 50% of the board edge space, even more than the line spacing or 2.5mm, depending on both the smaller; appeared to break loose the edge.

3 white side

Acceptance: encroachment white circle to the nearest edge of the board were not affected conductor distance, yet reduction to 50% or 2.5mm, depending on the lesser of the two.

Failure: white border encroachment to the nearest edge of the board were not affected conductor distance, has made the reduction of more than 50 %, or 2.5mm, depending on both the smaller.

4 weave exposure

Acceptance: effects of heat stress or mechanical stress caused by glass -sided beam splitter may not exceed 20% of the total area.

Failure: effects of heat stress or mechanical stress caused by the beam splitter glass -sided with a total area of more than 20%

Hole poor judgment

A plated tumor/feather

Acceptance: Chrome tumor/feather when not affect the minimum requirements may be allowed to close the aperture.

Failure: failure to meet minimum aperture when both failed.

2 hole broken

Acceptance: Any hole in the wall of the hole no more than one full plate has a hole through holes in the number nor more than 5 % of any holes that appear not exceeded 5% of the hole length; hole nor more than a quarter of the circumference.

Failure: flaws beyond the above criteria are not qualified.

3 pink ring pink ring no effect on the function of signs, are allowed to close.

4 Not plated hole edge white circle

Acceptance: caused by a white circle (defects) or edge into hierarchical, yet down to the nearest edge of the hole conductor has 50 % of the distance, when you can not express if not more than 2.5mm.

Failure: failure defects beyond the above criteria are

Goldfinger bad judgment

Lu Ni/exposed copper/depression/pit

Acceptance: In certain key areas of the finger (usually the middle 3/5) shortcomings exposed base metal has not yet occurred; specific contact area in the middle of each finger, did not splash of tin or tin-lead traces appear; each middle finger specific contact area of the tumor appears or metal bump junction still protruding from the surface ; recessed pit area and its subsidence over yet other maximum size 0.8mm, the disadvantages of each of these pieces to be more than three fingers, this is Disadvantages hand index can not exceed 30% of the total.

Failure: the shortcomings that appears over each of the above criteria are unqualified

Text/Symbol poor judgment

1 .General acceptance specifications mark

Acceptance: the code lines have been broken, but still shaped interpretation; Although the code into an empty area was stained coating, can still be identified without confusion by other code.

Failure: the font tag has been lost or unreadable ; hollow area code has been unable to interpret or dip coating may be misreading the font lines have mold burnt, broken or lost.

2 etched mark

Acceptance: After the tape by 3M 600 # tear proof of good adhesion of the coating, the coating did not show off.

Failure: the failure to meet the requirements of etching marks listed above.

Solder Mask poor judgment

1 . Were missing voids / exposed wires

Acceptance: Lucy were missing the front lines are not allowed , to allow one-way side exposed copper 0.5mm (20mil) must not exceed the following exposed copper (with) two adjacent lines are not exposed copper may allow 2cm or less

Failure: failure to comply with the above requirements are substandard.

2 Solder Mask of accuracy for trepanning

Acceptance: masking aperture ring on the resist has been inaccurate, but this has not been distorted out of masking ring width violate minimum quality requirements; especially for welding as vias, the green paint did not enter the cell wall has not been exposed isolated adjacent pad or wire.

Failure: failure to comply with the above requirements are substandard.

3 sets of BGA pad of accuracy:

Acceptance: green paint pad misalignment caused by breaking the surface without paint were not yet over a quarter of the perimeter ( ie, 90 °).

4 solder paint blistering stratification

Acceptance: this drawback does not exceed 0.25mm (0.00984 ") and each board can only occur two, electrically isolated from its reduced spacing should not exceed 25%.

Failure: If the above criteria are failed over shortcomings.

5 After the solder paint adhesion tape test --3M 600 #, floating green paint of the series from 6010 has not exceeded the limits allowed by the specification of acceptance, floating over green paint over the limit, compared with unqualified away.

Line & flatness determination

1 line gap pinhole - rough scratches

Acceptance : isolated line edge roughness gap-pinholes caused by a variety of substrates, although comprehensive scratching of exposure , at least as long as the width is not reduced to less than 20% were reached , it can be allowed to close. Under no circumstances such reduction ( line edge roughness-gap , etc.) must not exceed the line length respects 13mm, or 10% of the line length, whichever is smaller as the digitally dependent objects.

2 Alice plate bending & Board

Circuit board for surface -mount, the plate bending plate Alice-not exceed 0.75 percent , as its warped other board should not exceed 1.5%.

Source://www.seekic.com

Join us
Wanna be a dedicated PCBWay writer? We definately look forward to having you with us.
  • Comments(0)
You can only upload 1 files in total. Each file cannot exceed 2MB. Supports JPG, JPEG, GIF, PNG, BMP
0 / 10000
    Back to top