AMMC-5618 Datasheet, PDF (6/8 Pages) Agilent(Hewlett-Packard) – 6 - 20 GHz Amplifier

Biasing and Operation
The AMMC- 5618 is normally
biased with a single positive
drain supply connected to both
V_D1 and V_D2 bond pads as
shown in Figure 19(a). The
recommended supply voltage is
3 to 5 V.
No ground wires are required
because all ground connections
are made with plated through-
holes to the backside of the
device.
Gate bias pads (V_G1 & V_G2) are
also provided to allow
adjustments in gain, RF output
power, and DC power
dissipation, if necessary. No
connection to the gate pad is
needed for single drain- bias
operation. However, for custom
applications, the DC current
flowing through the input and/
or output gain stage may be
adjusted by applying a voltage
to the gate bias pad(s) as shown
in Figure 19(b). A negative gate-
pad voltage will decrease the
drain current. The gate- pad
voltage is approximately zero
volt during operation with no
DC gate supply. Refer to the
Absolute Maximum Ratings
table for allowed DC and
thermal conditions.
Assembly Techniques
The backside of the AMMC- 5618
chip is RF ground. For
microstripline applications, the
chip should be attached directly
to the ground plane (e.g., circuit
carrier or heatsink) using
electrically conductive epoxy^[1].
For best performance, the
topside of the MMIC should be
brought up to the same height
as the circuit surrounding it.
This can be accomplished by
mounting a gold plated metal
shim (same length and width as
the MMIC) under the chip,
which is of the correct
thickness to make the chip and
adjacent circuit coplanar.
The amount of epoxy used for
chip and or shim attachment
should be just enough to
provide a thin fillet around the
bottom perimeter of the chip or
shim. The ground plane should
be free of any residue that may
jeopardize electrical or
mechanical attachment.
The location of the RF bond
pads is shown in Figure 20.
Note that all the RF input and
output ports are in a Ground-
Signal- Ground configuration.
RF connections should be kept
as short as reasonable to
minimize performance
degradation due to undesirable
series inductance. A single bond
wire is sufficient for signal
connections, however double-
bonding with 0.7 mil gold wire
or the use of gold mesh^[2] is
recommended for best
performance, especially near the
high end of the frequency range.
76 ± 8 mS. A guided wedge at an
ultrasonic power level of 64 dB
can be used for the 0.7 mil wire.
The recommended wire bond
stage temperature is 150 ± 2° C.
Caution should be taken to not
exceed the Absolute Maximum
Rating for assembly temperature
and time.
The chip is 100 µm thick and
should be handled with care. This
MMIC has exposed air bridges on
the top surface and should be
handled by the edges or with a
custom collet (do not pick up die
with vacuum on die center.)
This MMIC is also static
sensitive and ESD handling
precautions should be taken.
Notes:
1. Ablebond 84-1 LM1 silver epoxy is
recommended.
2. Buckbee-Mears Corporation, St. Paul, MN,
800-262-3824
Thermosonic wedge bonding is
the preferred method for wire
attachment to the bond pads.
Gold mesh can be attached using
a 2 mil round tracking tool and a
tool force of approximately 22
grams with an ultrasonic power
of roughly 55 dB for a duration of
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