A reading of the pictures is: A1: Looks like pad [B1] is smaller than the other pads. It�s weird that the pads are such different colors. A2: Looks like pad [B1] is smaller than the other pads. Solder mask opening [B1] is misregistered and seems smaller than other openings. Solder mask seems very thick, relative to the pad thickness. B1: Silk screen is closer to the pads than A1 and C1. B2: Silk screen is closer to the pads than A1 and C1. B3: All solder paste is misregistered in printing. Amount of paste for pad [B1] is smaller than the amount for other pads. C1: ~ C2: Several solder bumps [A1, A4, B4, C1, C4, D4] seem larger than other bumps. Solder mask appears to be poorly adhered in several locations [A2/A3, B3/C3, C2/C3, D2/D3]. D1: Pad does not accept solder. Solder bumps vary in size. Solder mask misregistered. Solder mask seems very thick, relative to the pad thickness. D2: As in D1. Do not see �wicking to adjacent pad� that Matt mentioned. E1: Several flattened solder areas [A1, A2, A4, B4, C2, D2, D4] appear larger than other areas. These larger areas do not correspond with large solder bumps mentioned in C2, because the pictures [C2 and E1] are of different boards. Silk screen is closer to the pads than A1 and C1. F1: Two corroded pads. Pads appear to be present with the corrosion sitting on the surface. Solder mask seems very thick, relative to the pad thickness. F2: Unattached to the board, two pads with excess solder that connect them together.
While there seems to ample points to criticize this board design and fabrication, the more distressing faults are: * D1: Pad does not accept solder. Does this go back to the discolored gold on pads in A1? Could the gold plating be thin enough to allow the nickel underplate to become unsolderable? Alternately, it�s tough to say, but the pad still appears to be gold colored, indicating that solder never touched the pad. That could be caused by poor solder paste printing process or residual solder mask bleed remaining on the pad. * F1: Two corroded pads. This corrosion appears to on top of the pads. Is this a function of either poor plating or process materials being retained in deep solder mask �wells�? What is the composition of the brown coarse residue in the solder mask well? * F2: Unattached to the board, two pads � The laminate to pad surface appears smooth and with no signs of over etching. Could this be caused by poor laminate to pad adhesion? Are other pads �falling-off�?
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