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(a) SLM circuit board
(b) SLM board (with components)
Figure B.7 : (a) The SLM circuit board has a 34 mm × 34 mm square hole surrounded
by 1040 gold bond fingers, designed to mount and to wire-bond the SLM chip, (b)
Besides the SLM chip, the SLM circuit board also has 24 cable connectors which
receives voltage-amplified control signals from the line driver circuit.
B.5 SLM board
The SLM board is the interface between the SLM control circuit and the SLM chip,
designed to fit the constraints in the wire-bonding procedures and to move around
easily while conducting experiments.
As shown in Figure B.7, the SLM board, 4.5” × 4.5” in size and 40-mil thick, has
a 34 mm × 34 mm square hole in the middle, surrounded by 260 gold bond fingers on
each side of the square. Each bond fingers are 5 mils × 20 mils and are electroplated
with 60 microinches of soft bondable gold. Four 4-40 screw holes at the four corners
of the square hole are useful for fixing the board in position during wire-bonding,
and for an add-on transparent plastic case for chip protection. The distance from
one side of the square hole to the edge of the board is around 1.5”, which must be