AWG G3 PAD FOR PS3 Dokumentacja Pobierz pdf (Strona 116)

5 DUT Board Performance Considerations Signal Traces

116 System Reference, January 2001

Signal Traces

Landing holes/vias are inside the landing pads. The via-in-

pad method provides better contact reliability than pogo-

on-surface methods.

High-Frequency Testing Testing at high frequencies requires an impedance-

matched environment. The board should therefore be

designed to match the tester impedance. For proper oper-

ation, the impedance specification of 50 Ω ±10% must be

met. We recommend that you use the inner part of the

board for the high-speed traces. In this area, the process

tolerances are usually tighter, resulting in a better imped-

ance matching.

A minimum trace width of 12 mil (0.3 mm) is recom-

mended. The wider the trace width, the lower the attenua-

tion and skin effects.

Line Insulation All signal and ground lines and pads on the board must be

insulated from the stiffener. If signal lines or pads are

placed on the board’s surface that touches the stiffener, an

insulation sheet must be inserted between stiffener and

board (max. thickness 0.2 mm). Do not exceed this thick-

ness, as the sheet reduces the pogo travel. Recommended

material is Epoxy F40 or similar. Before selecting the

material, check whether the stiffener will be used at

extreme hot or cold temperatures.Without insulation,

these signal lines may either short on or inductively

couple to the stiffener. Milling of these areas on the stiff-

ener is not advised since this weakens the mechanical

stability of the assembly.

Dummy Pads For compatibility with future upgrades, the associated

pogo area should be free of any contacts or parts on the

bottom of the DUT board. We recommend that you add

dummy pads so that the DUT board is usable on systems

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AWG G3 PAD FOR PS3 Dokumentacja Strona 116