HMMC-3102 Datasheet, PDF (4/8 Pages) Agilent(Hewlett-Packard) – DC - 16 GHz Packaged Divide-by-2 Prescaler

Input dc Offset
If an RF signal with sufficient signal
to noise ratio is present at the RF
input lead, the prescaler will operate
and provide a divided output equal the
input frequency divided by the divide
modulus. Under certain "ideal" condi-
tions where the input is well matched
at the right input frequency, the com-
ponent may “self-oscillate”, especially
under small signal input powers or
with only noise present at the input
This “self-oscillation” will produce a
undesired output signal also known
as a false trigger. To prevent false
triggers or self-oscillation conditions,
apply a 20 to 100 mV dc offset voltage
between the RF_in and RF_in ports. This
prevents noise or spurious low level
signals from triggering the divider.
Adding a 10 kΩ resistor between the
unused RF input to a contact point at
the V_EE potential will result in an offset
of ≈ 25 mV between the RF inputs.
Note however, that the input sensitiv-
ity will be reduced slightly due to the
presence of this offset.
Figure 1. Simplified Schematic
Assembly Notes
Independent of the bias applied to the
package, the backside of the package
should always be connected to both
a good RF ground plane and a good
thermal heat sinking region on the
PC board to optimize performance.
For single-ended output operation the
unused RF output lead should be ter-
minated into 50 Ω to a contact point
at the V_CC potential or to RF ground
through a dc blocking capacitor.
A minimum RF and thermal PC board
contact area equal to or greater than
2.67 × 1.65 mm (0.105" × 0.065") with
eight 0.020" diameter plated-wall
thermal vias is recommended.
MMIC ESD precautions, handling con-
siderations, die attach and bonding
methods are critical factors in
successful GaAs MMIC performance
and reliability.
Agilent application note #54, "GaAs
MMIC ESD, Die Attach and Bonding
Guidelines" provides basic information
on these subjects.
Moisture Sensitivity Classification:
Class 1, per JESD22-A112-A.
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