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TM 9-254
4-17. Printed Circuit Board - Continued
j.
Flat Pack and Dual-In-Line Pack (DIP) ICs.
(1)
Flat Pack. They are planar mounted on the surface of the board to form lap solder joint connections. The
specification for round leads will be observed with these additions:
(a)
The leads will contain two distinct bends at an approximate angle of 45°
(b)
The leads will contact the solder pad from the second bend to the lead tip
(c)
The contact area will not overhang the edge of the solder pad
(d)
The contact area of the lead will be one-half the length of the solder pad
(2)
Dual-In-Line Packs (DIPs). They are mounted through the surface of the board and soldered in place. The
specification for round leads will be observed with these additions:
Figure 4-44.1. Typical Paner Mounted IC
(a)
Form the leads by pressing both rows of leads down onto a flat surface with enough pressure to obtain the
correct angle. Another method is the use of a DIP clip that holds the leads inward for installation.
(b)
Clinch the two leads on opposite corners to hold the IC in place.
(c)
Apply iron tip to one side of the joint touching the lead and pad area, while applying solder to the opposite
side.
(d)
Apply iron until solder pool flows into hole to produce a smooth, concave fillet.
4-46 Change 6
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