HPMD7904TR1 Avago Technologies US Inc., HPMD7904TR1 Datasheet - Page 8

• Manufacturer Part Number: HPMD7904TR1
• Manufacturer: Avago Technologies US Inc.

Specifications of HPMD7904TR1

• Pin Count: 3
• Screening Level: Commercial
• Lead Free Status / Rohs Status: Not Compliant

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pads are provided on the top surface, extending be-
yond the edges of the duplexer (Figure 19). These are
connected to the buried stripline conductors by
means of two plated and plugged via holes (each).
In this buried layer, the three lines are isolated by
large ground areas, connected to the ground plane
above and below. This provides for the best contain-
ment of transmission line fields.
Figure 19. Top layer for stripline realization.
Figure 20. Buried layer for stripline realization.
Solder Mask and Solder Stencil
Solder mask is used on all motherboards, to prevent
solder from adhering to places where it is not desired.
In mounting the duplexer, it serves as an aid to align-
ment during wave soldering.
The motherboard solder mask (shown in green in
Figures 18 and 19) should correspond to the edges of
the duplexer. This will contain the solder during
reflow, and prevent the duplexer from rotating or slip-
ping out of alignment.
A solder stencil is used to print a pattern of solder
paste onto the motherboard, with the duplexer placed
upon this paste before the reflow process begins. The
design of the solder stencil is critical to obtaining good
yields in reflow soldering.