250
200
TMAX
150
100
Reflow
Zone
Preheat
Zone
Cool Down
Zone
50
0
0
60
120
180
240
300
TIME (seconds)
Figure 23. Surface Mount Assembly Profile.
These parameters are typical for a
surface mount assembly process
for the MGA-81563. As a general
guideline, the circuit board and
components should be exposed
only to the minimum tempera-
tures and times necessary to
achieve a uniform reflow of
solder.
The MGA-81563 is has been
qualified to the time-temperature
profile shown in Figure 23. This
profile is representative of an IR
reflow type of surface mount
assembly process.
After ramping up from room
temperature, the circuit board
with components attached to it
(held in place with solder paste)
passes through one or more
Electrostatic Sensitivity
GaAs MMICs are
preheat zones. The preheat zones
increase the temperature of the
board and components to prevent
thermal shock and begin evaporat-
ing solvents from the solder paste.
The reflow zone briefly elevates
the temperature sufficiently to
produce a reflow of the solder.
electrostatic discharge
(ESD) sensitive
devices. Although the
MGA-81563 is robust in design,
permanent damage may occur to
these devices if they are subjected
to high energy electrostatic
discharges. Electrostatic charges
as high as several thousand volts
(which readily accumulate on the
human body and on test equip-
ment) can discharge without
detection and may result in
degradation in performance or
failure. The MGA-81563 is an ESD
Class 1 device. Therefore, proper
ESD precautions are recom-
mended when handling, inspect-
ing, and assembling these devices
to avoid damage.
The rates of change of tempera-
ture for the ramp-up and cool-
down zones are chosen to be low
enough to not cause deformation
of the board or damage to compo-
nents due to thermal shock. The
maximum temperature in the
reflow zone (T
) should not
MAX
exceed 235 °C.
6-205
AGILENT [ AGILENT TECHNOLOGIES, LTD. ]
