HMMC-3108-BLK HP [Agilent(Hewlett-Packard)], HMMC-3108-BLK Datasheet - Page 4

• Manufacturer Part Number: HMMC-3108-BLK
• Description: DC-16 GHz Packaged Divide-by-8
• Manufacturer: HP [Agilent(Hewlett-Packard)]

Applications
The HMMC-3108 is designed for
use in high frequency
communications, microwave
instrumentation, and EW radar
systems where low phase–noise
PLL control circuitry or broad–
band frequency translation is
required.
Operation
The device is designed to
operate when driven with either
a single–ended or differential
sinusoidal input signal over a
200 MHz to 16 GHz bandwidth.
Below 200 MHz the prescaler
input is “slew–rate” limited,
requiring fast rising and falling
edge speeds to properly divide.
The device will operate at
frequencies down to dc when
driven with a square–wave.
Due to the presence of an off–
chip RF–bypass capacitor inside
the package (connected to the
V
the unique design of the device
itself, the component may be
biased from either a single
positive or single negative
supply bias. The backside of the
package is not dc connected to
any dc bias point on the device.
Figure 1. Simplified Schematic
4
IN
IN
CC
contact on the device), and
5
7
SOIC8 w/Backside GND
By
poss
IN
IN
50
V
6
V cc
CC
50
150p
For positive supply operation,
V
any voltage in the +4.5 to +6.5
volt range with pin 8 (V
grounded. For negative bias
operation V
grounded and a negative voltage
between - 4.5 to - 6.5 volts is
applied to pin 8 (V
ac–Coupling and dc–Blocking
All RF ports are dc connected
on–chip to the V
through on–chip 50W resistors.
Under any bias conditions where
V
ports should be ac coupled via
series capacitors mounted on
the PC– board at each RF port.
Only under bias conditions
where V
typical for negative bias supply
operation) may the RF ports be
direct coupled to adjacent
circuitry or in some cases, such
as level shifting to subsequent
stages. In the latter case the
package heat sink may be
“floated” and bias applied as the
difference between V
V
CC
C C
4
V
V cc
8
CC
V ee
÷
EE
is not dc grounded the RF
pins are nominally biased at
CC
is dc grounded (as is
CC
pins are typically
50
V
2
CC
V cc
CC
Vpwr
sel
EE
contact
CC
).
50
OUT
OUT
EE
and V
)
EE
.
3
Pin 1
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”
conditions where the input is
well matched at the right input
frequency, the component may
“self–oscillate”, especially under
small signal input powers or
with only noise present at the
input. This “self–oscillation” will
produce an 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 RFi n and
RFi n ports. This prevents noise
or spurious low level signals
from triggering the divider.
Adding a 10KW resistor between
the unused RF input to a contact
point at the VEE potential will
result in an offset of » 25mV
between the RF inputs. Note,
however, that the input
sensitivity will be reduced
slightly due to the presence of
this offset.
OUT
OUT