ANAREN XMC2560E-03

Model XMC2560E-03
Rev B
Wideband Hybrid Coupler, 3 dB, 90°
Military Grade
Description
The XMC2560E-03 is a low profile, high performance 3dB hybrid coupler in
an easy to use, manufacturing friendly surface mount package. It is designed
primarily for defense applications. The XMC2560E-03 is designed particularly
for balanced power and low noise amplifiers, plus signal distribution and other
applications where low insertion loss and tight amplitude and phase balance
is required. It can be used in high power applications up to 100 watts.
Parts have been subjected to rigorous qualification testing and they are
manufactured using materials with coefficients of thermal expansion (CTE)
compatible with common substrates such as FR4, G-10, RF-35, RO4350 and
polyimide.
Electrical Specifications **
Features:
• 2500 – 6000 MHz
• Defense Applications
• High Power
• Very Low Loss
• Tight Amplitude Balance
• High Isolation
• Production Friendly
• Tape and Reel
• Available in Lead-Free (as
illustrated) or Tin-Lead
• Reliable, FIT=0.53
Frequency
Isolation
Insertion
Loss
VSWR
Amplitu
de
Balance
MHz
dB Min
dB Max
Max : 1
dB Max
2500-6000
21
0.22
1.25
± 0.75
Phase
Error
Power
Degrees
Avg. CW Watts
ºC/Watt
ºC
± 4.0
TBD
39
-55 to +95
ΘJC
Operating
Temp.
**Specification based on performance of unit properly installed on Anaren Test Board 54606-0003 with small
signal applied. Specifications subject to change without notice. Refer to parameter definitions for details.
Bottom View
Side View
Top View
.089±.009
[2.25±0.22]
Pin 1
.560±.010
[14.22±0.25]
.200±.010
[5.08±0.25]
GND
Pin 4
Pin 2
Denotes
Array Number
Pin 3
Pin 2
.025±.004
[0.64±0.10]
.042±.004 SQ
[1.07±0.10]
GND
Pin 3
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Pin 1
.042±.004 SQ
[1.07±0.10]
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Model XMC2560E-03
Rev B
Hybrid Coupler Pin Configuration
The XMC2560E-03 has an orientation marker to denote Pin 1. Once port one has been identified the other ports are
known automatically. Please see the chart below for clarification:
Configuration
Splitter
Splitter
Splitter
Splitter
Pin 1
Input
Isolated
Pin 2
Isolated
Input
-3dB ∠θ − 90
-3dB ∠θ
-3dB ∠θ
-3dB ∠θ − 90
*Combiner
*Combiner
*Combiner
*Combiner
A ∠θ − 90
A ∠θ
Isolated
Output
A ∠θ
A ∠θ − 90
Output
Isolated
Pin 3
-3dB ∠θ − 90
-3dB ∠θ
Input
Isolated
Pin 4
-3dB ∠θ
-3dB ∠θ − 90
Isolated
Input
Isolated
Output
Output
Isolated
A ∠θ − 90
A ∠θ
A ∠θ
A ∠θ
− 90
*Note: “A” is the amplitude of the applied signals. When two quadrature signals with equal amplitudes are
applied to the coupler as described in the table, they will combine at the output port. If the amplitudes are
not equal, some of the applied energy will be directed to the isolated port.
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Model XMC2560E-03
Rev B
XMC2560E-03 Typical Performance
Isolation
0
S11
-5
S22
-10
S33
-15
0
S21
-5
S43
-10
S44
-15
Isolation [dB]
Return Loss [dB]
Return Loss
-20
-25
-30
-20
-25
-30
-35
-35
-40
-40
-45
-45
-50
-50
2500
3000
3500
4000
4500
5000
5500
2500
6000
3000
4000
4500
5000
5500
5000
5500
6000
Frequency [MHz]
Frequency [MHz]
Coupling
Insertion Loss
-2.0
0
S31
-2.2
-0.05
S41
-2.4
-0.1
Insertion Loss [dB]
-2.6
Coupling [dB]
3500
-2.8
-3.0
-3.2
-3.4
-0.15
-0.2
-0.25
-0.4
-3.8
-0.45
-4.0
-0.5
3000
3500
4000
4500
5000
5500
6000
S42+S32
-0.35
-3.6
2500
S31+S41
-0.3
2500
3000
3500
4000
4500
6000
Frequency [MHz]
Frequency [MHz]
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Rev B
Amplitude Balance
Phase Error from Quadrature
1.0
S31
S41
0.6
0.4
0.2
0.0
-0.2
-0.4
-0.6
S32 - S42 - 90º
2
1
0
-1
-2
-3
-0.8
-4
-1.0
2500
S41 - S31 - 90º
4
3
Difference [deg]
Amplitude Balance [dB]
0.8
5
-5
3000
3500
4000
4500
5000
5500
6000
Frequency [MHz]
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2500
3000
3500
4000
4500
Frequency [MHz]
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5000
5500
6000
Model XMC2560E-03
Rev B
Definition of Measured Specifications
Parameter
Definition
VSWR
(Voltage Standing Wave Ratio)
The impedance match of
the coupler to a 50Ω
system. A VSWR of 1:1 is
optimal.
Return Loss
Insertion Loss
Isolation
Phase Error (From Quadrature)
Amplitude Balance
Mathematical Representation
The impedance match of
the coupler to a 50Ω
system. Return Loss is
an alternate means to
express VSWR.
The input power divided
by the sum of the power
at the two output ports.
The input power divided
by the power at the
isolated port.
The difference in phase
angle between the two
output ports minus 90o.
The power at each output
divided by the average
power of the two outputs.
VSWR =
Vmax
Vmin
Vmax = voltage maxima of a standing wave
Vmin = voltage minima of a standing wave
Return Loss (dB)= 20log
VSWR + 1
VSWR - 1
Insertion Loss(dB)= 10log
Pin
Pcpl + Pdirect
Isolation(dB)= 10log
Pin
Piso
(Phase at coupled port – Phase at direct port)
– 90o
10log
Pcpl
Pdirect
and 10log
⎛ Pcpl + Pdirect ⎞
⎛ Pcpl + Pdirect ⎞
⎜
⎟
⎜
⎟
2
2
⎝
⎠
⎝
⎠
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Notes on RF Testing and Circuit Layout
The XMC2560E-03 Surface Mount Couplers require the use of a test fixture for verification of RF performance. This
test fixture is designed to evaluate the coupler in the same environment that is recommended for installation.
Enclosed inside the test fixture, is a circuit board that is fabricated using the recommended footprint. The part being
tested is placed into the test fixture and pressure is applied to the top of the device using a pneumatic piston. A four
port Vector Network Analyzer is connected to the fixture and is used to measure the S-parameters of the part. Worst
case values for each parameter are found and compared to the specification. These worst case values are reported to
the test equipment operator along with a Pass or Fail flag. See the illustrations below.
3 & 5 dB
Test Board
10 & 20 dB
Test Board
Test Board
In Fixture
Test Station
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Rev B
The effects of the test fixture on the measured data must be minimized in order to accurately determine the
performance of the device under test. If the line impedance is anything other than 50Ω and/or there is a discontinuity
at the microstrip to SMA interface, there will be errors in the data for the device under test. The test environment can
never be “perfect”, but the procedure used to build and evaluate the test boards (outlined below) demonstrates an
attempt to minimize the errors associated with testing these devices. The lower the signal level that is being
measured, the more impact the fixture errors will have on the data. Parameters such as Return Loss and
Isolation/Directivity, which are specified as low as 27dB and typically measure at much lower levels, will present the
greatest measurement challenge.
The test fixture errors introduce an uncertainty to the measured data. Fixture errors can make the performance of the
device under test look better or worse than it actually is. For example, if a device has a known return loss of 30dB and
a discontinuity with a magnitude of –35dB is introduced into the measurement path, the new measured Return Loss
data could read anywhere between –26dB and –37dB. This same discontinuity could introduce an insertion phase
error of up to 1°.
There are different techniques used throughout the industry to minimize the affects of the test fixture on the
measurement data. Anaren uses the following design and de-embedding criteria:
•
Test boards have been designed and parameters specified to provide trace impedances of 50
±1Ω. Furthermore, discontinuities at the SMA to microstrip interface are required to be less than
–35dB and insertion phase errors (due to differences in the connector interface discontinuities
and the electrical line length) should be less than ±0.25° from the median value of the four
paths.
•
A “Thru” circuit board is built. This is a two port, microstrip board that uses the same SMA to
microstrip interface and has the same total length (insertion phase) as the actual test board. The
“Thru” board must meet the same stringent requirements as the test board. The insertion loss
and insertion phase of the “Thru” board are measured and stored. This data is used to
completely de-embed the device under test from the test fixture. The de-embedded data is
available in S-parameter form on the Anaren website (www.anaren.com).
Note: The S-parameter files that are available on the anaren.com website include data for frequencies that are
outside of the specified band. It is important to note that the test fixture is designed for optimum performance through
6GHz. Some degradation in the test fixture performance will occur above this frequency and connector interface
discontinuities of –25dB or more can be expected. This larger discontinuity may affect the data at frequencies above
6GHz.
Circuit Board Layout
The dimensions for the Anaren test board are shown below. The test board is printed on Rogers RO4003 material
that is 0.020” thick. Consider the case when a different material is used. First, the pad size must remain the same to
accommodate the part. But, if the material thickness or dielectric constant (or both) changes, the reactance at the
interface to the coupler will also change. Second, the line width required for 50Ω will be different and this will
introduce a step in the line at the pad where the coupler interfaces with the printed microstrip trace. Both of these
conditions will affect the performance of the part. To achieve the specified performance, serious attention must
be given to the design and layout of the circuit environment in which this component will be used.
If a different circuit board material is used, an attempt should be made to achieve the same interface pad reactance
that is present on the Anaren RO4003 test board. When thinner circuit board material is used, the ground plane will
be closer to the pad yielding more capacitance for the same size interface pad. The same is true if the dielectric
constant of the circuit board material is higher than is used on the Anaren test board. In both of these cases,
narrowing the line before the interface pad will introduce a series inductance, which, when properly tuned, will
compensate for the extra capacitive reactance. If a thicker circuit board or one with a lower dielectric constant is used,
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the interface pad will have less capacitive reactance than the Anaren test board. In this case, a wider section of line
before the interface pad (or a larger interface pad) will introduce a shunt capacitance and when properly tuned will
match the performance of the Anaren test board.
The entry angle of the traces has a
significant impact on the RF performance
and these parts have been optimized for the
layout used on the test boards shown
below.
Testing Sample Parts Supplied on Anaren Test Boards
If you have received a coupler installed on an Anaren produced microstrip test board, please remember to remove the
loss of the test board from the measured data. The loss is small enough that it is not of concern for Return Loss and
Isolation/Directivity, but it should certainly be considered when measuring coupling and calculating the insertion loss
of the coupler. An S-parameter file for a “Thru” board (see description of “Thru” board above) will be supplied upon
request. As a first order approximation, one should consider the following loss estimates:
Frequency Band
2500 MHz
4000 MHz
6000 MHz
Avg. Ins. Loss of Test Board @ 25°C
~ 0.29dB
~ 0.41dB
~ 0.57dB
For example, a 4300MHz, 10dB coupler on a test board may measure –10.60dB from input to the coupled port at
frequency F1=4000 MHz. When the loss of the test board is removed, the coupling at F1 becomes -10.19dB (10.60dB + 0.41dB). This compensation must be made to both the coupled and direct path measurements when
calculating insertion loss.
The loss estimates in the table above come from room temperature measurements. It is important to note that the
loss of the test board will change with temperature. This fact must be considered if the coupler is to be evaluated at
other temperatures.
Orientation Marker
A printed circular feature appears on the top surface of the coupler to designate Pin 1. This orientation marker is not
intended to limit the use of the symmetry that these couplers exhibit but rather to facilitate consistent placement of
these parts into the tape and reel package. This ensures that the components are always delivered with the same
orientation. Refer to the table on page 2 of the data sheet for allowable pin configurations.
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Rev B
Mounting
Coupler Mounting Process
In order for Xinger surface mount couplers to work
optimally, there must be 50Ω transmission lines leading
to and from all of the RF ports. Also, there must be a
very good ground plane underneath the part to ensure
proper electrical performance. If either of these two
conditions is not satisfied, insertion loss, coupling, VSWR
and isolation may not meet published specifications.
Overall ground is improved if a dense population of
plated through holes connect the top and bottom ground
layers of the PCB. This minimizes ground inductance
and improves ground continuity. All of the Xinger hybrid
and directional couplers are constructed from ceramic
filled PTFE composites which possess excellent electrical
and mechanical stability having X and Y thermal
coefficient of expansion (CTE) of 17-25 ppm/oC.
When a surface mount hybrid coupler is mounted to a
printed circuit board, the primary concerns are; ensuring
the RF pads of the device are in contact with the circuit
trace of the PCB and insuring the ground plane of neither
the component nor the PCB is in contact with the RF
signal.
Mounting Footprint
To ensure proper electrical and thermal
performance there must be a ground plane with
100% solder connection underneath the part
The process for assembling this component is a
conventional surface mount process as shown in Figure
1. This process is conducive to both low and high volume
usage.
Figure 1: Surface Mounting Process Steps
Storage of Components: The Xinger products are
available in either an immersion tin or tin-lead finish.
Commonly used storage procedures used to control
oxidation should be followed for these surface mount
components. The storage temperatures should be held
between 15OC and 60OC.
Substrate: Depending upon the particular component,
the circuit material has an x and y coefficient of thermal
expansion of between 17 and 25 ppm/°C. This coefficient
minimizes solder joint stresses due to similar expansion
rates of most commonly used board substrates such as
RF35, RO4350, FR4, polyimide and G-10 materials.
Mounting to “hard” substrates (alumina etc.) is possible
depending upon operational temperature requirements.
The solder surfaces of the coupler are all copper plated
with either an immersion tin or tin-lead exterior finish.
Solder Paste: All conventional solder paste formulations
will work well with Anaren’s Xinger II surface mount
components. Solder paste can be applied with stencils or
syringe dispensers. An example of a stenciled solder
paste deposit is shown in Figure 2. As shown in the
figure solder paste is applied to the four RF pads and the
entire ground plane underneath the body of the part.
Dimensions are in Inches [Millimeters]
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Reflow: The surface mount coupler is conducive to most of
today’s conventional reflow methods. A low and high
temperature thermal reflow profile are shown in Figures 5
and 6, respectively. Manual soldering of these components
can be done with conventional surface mount non-contact
hot air soldering tools. Board pre-heating is highly
recommended for these selective hot air soldering
methods. Manual soldering with conventional irons should
be avoided.
Figure 2: Solder Paste Application
Coupler Positioning: The surface mount coupler can
be placed manually or with automatic pick and place
mechanisms. Couplers should be placed (see Figure 3
and 4) onto wet paste with common surface mount
techniques and parameters. Pick and place systems
must supply adequate vacuum to hold a 0.50-0.55
gram coupler.
Figure 3: Component Placement
Figure 4: Mounting Features Example
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Figure 5 – Low Temperature Solder Reflow Thermal Profile
Figure 6 – High Temperature Solder Reflow Thermal Profile
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Application Information
The XMC2560E-03 is an “X” style 3dB (hybrid) coupler. Port configurations are defined in the table on page 2 of this
data sheet and an example driving port 1 is shown below.
Ideal 3dB Coupler Splitter Operation
1V
Isolated Port
1
4
0.707V∠θ (-3dB)
2
3
0.707V ∠θ -90 (-3dB)
The hybrid coupler can also be used to combine two signals that are applied with equal amplitudes and phase
quadrature (90º phase difference). An example of this function is illustrated below.
Ideal 3dB Coupler Combiner Operation
0.707V∠θ
0.707V ∠θ -90
1
4
Isolated Port
2
3
1V∠Φ
3dB couplers have applications in circuits which require splitting an applied signal into 2, 4, 8 and higher binary
outputs. The couplers can also be used to combine multiple signals (inputs) at one output port. Some splitting and
combining schemes are illustrated below:
2-Way Splitter/Combiner Network
Input
Amplitude and
Phase tracking
Devices
* 50Ω
Termination
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* 50Ω
Termination
Output
Model XMC2560E-03
Rev B
4-Way Splitter/Combiner Network
Amplitude and
Phase tracking
Devices
Input
* 50Ω
Termination
* 50Ω
Termination
* 50Ω
Term.
* 50Ω
Termination
Amplitude and
Phase tracking
Devices
Output
* 50Ω
Termination
* 50Ω
Term.
n
The splitter/combiner networks illustrated above use only 3dB (hybrid) couplers and are limited to binary divisions (2
number of splits, where n is an integer). Splitter/combiner circuits configured this way are known as “corporate”
networks. When a non-binary number of divisions is required, a “serial” network must be used. Serial networks can be
designed with [3, 4, 5, ….., n] splits, but have a practical limitation of about 8 splits.
A 5dB coupler is used in conjunction with a 3dB coupler to build 3-way splitter/combiner networks. An ideal version of
this network is illustrated below. Note what is required; a 50% split (i.e. 3dB coupler) and a 66% and 33% split (which is
actually a 4.77dB coupler, but due to losses in the system, higher coupler values, such as 5dB, are actually better
suited for this function). The design of this type of circuit requires special attention to the losses and phase lengths of
the components and the interconnecting lines. A more in depth look at serial networks can be found in the article
“Designing In-Line Divider/Combiner Networks” by Samir Tozin, which describes the circuit design in detail and can be
found in the White Papers Section of the Anaren website, www.anaren.com.
3-Way Splitter/Combiner
Pin
5 dB (4.77)
coupler
1/3 Pin
1/3 Pin
* 50Ω
Termination
3 dB coupler
G=1
2/3 Pin
* 50Ω
Termination
1/3 Pin
2/3 Pin
1/3 Pin
G=1
3 dB coupler
* 50Ω
Termination
* 50Ω
Termination
5 dB (4.77)
coupler
1/3 Pin
1/3 Pin
Pout
G=1
*Recommended Terminations
Power (Watts)
Model
8
RFP-060120A15Z50
15
RFP-250375A4Z50
50
RFP-375375A6Z50
100
RFP-500500A6Z50
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Reflections From Equal Unmatched Terminations
Referring to the illustration below, consider the following reflection properties of the 3dB coupler. A signal applied to
port 1 is split and appears at the two output ports, ports 3 & 4, with equal amplitude and in phase quadrature. If ports
3 & 4 are not perfectly matched to 50Ω there will be some signal reflected back into the coupler. If the magnitude and
angle of these reflections are equal, there will be two signals that are equal in amplitude and in phase quadrature (i.e.
the reflected signals) being applied to ports 3 & 4 as inputs. These reflected signals will combine at the isolated port
and will cancel at the input port. So, terminations with the same mismatch placed at the outputs of the 3dB coupler will
not reflect back to the input port and therefore will not affect input return loss.
Γ× 0.707V ∠θ
Γ (0.5V ∠2θ + 0.5V ∠2θ -180) = 0V
0.707V∠θ (-3dB)
4
1V
Termination = ZL
1
Γ=
Isolated Port
2
ZL − Z 0
ZL + Z 0
Termination = ZL
3
|Γ (0.5V ∠2θ -90 + 0.5V ∠2θ -90)| = |Γ|
0.707V ∠θ -90 (-3dB)
Γ× 0.707V ∠θ -90
The reflection property of common mismatches in 3dB couplers is very beneficial to the operation of many networks.
For instance, when splitter/combiner networks are employed to increase output power by paralleling transistors with
similar reflection coefficients, input return loss is not degraded by the match of the transistor circuit. The reflections
from the transistor circuits are directed away from the input to the termination at the isolated port of the coupler.
This example is not limited to Power Amplifiers. In the case of Low Noise Amplifiers (LNA’s), the reflection property of
3dB couplers is again beneficial. The transistor devices used in LNA’s will present different reflection coefficients
depending on the bias level. The bias level that yields the best noise performance does not also provide the best
match to 50 Ω. A circuit that is optimized for both noise performance and return loss can be achieved by combining
two matched LNA transistor devices using 3dB couplers. The devices can be biased for the best noise performance
and the reflection property of the couplers will provide a good match as described above. An example of this circuit is
illustrated below:
LNA Circuit Leveraging the Reflection Property of 3dB Couplers
50Ω
Termination
Input
50Ω
Termination
Energy reflected from LNA
devices biased for optimum
noise performance
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Amplitude and phase tracking
LNA devices biased for
optimum noise performance
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Signal Control Circuits Utilizing 3dB Couplers
Variable attenuators and phase shifter are two examples of signal control circuits that can be built using 3dB couplers.
Both of these circuits also use the reflection property of the 3dB coupler as described above. In the variable attenuator
circuit, the two output ports of a 3dB coupler are terminated with PIN diodes, which are basically a voltage variable
resistor at RF frequencies (consult the literature on PIN diodes for a more complete equivalent circuit). By changing the
resistance at the output ports of the 3dB coupler, the reflection coefficient, Γ, will also change and different amounts of
energy will be reflected to the isolated port (note that the resistances must change together so that Γ is the same for
both output ports). A signal applied to the input of the 3dB coupler will appear at the isolated port and the amplitude of
this signal will be a function of the resistance at the output ports. This circuit is illustrated below:
Variable Attenuator Circuit Utilizing a 3dB Coupler
Γ× 0.707V ∠θ
4
Input
1
Vdc
Output
0.707V∠θ (-3dB)
PIN Diodes
2
|Γ (0.5V ∠2θ -90 + 0.5V ∠2θ -90)| = |Γ|
and
|Output| = | Γ|×|Input|
3
0.707V ∠θ -90 (-3dB)
Γ× 0.707V ∠θ -90
If Γ=0, no energy is reflected from the PIN diodes and S21 = 0 (input to output). If | Γ | =1, all of the energy is reflected
from the PIN diodes and |S21| = 1 (assuming the ideal case of no loss). The ideal range for Γ is –1 to 0 or 0 to 1, which
translate to resistances of 0Ω to 50Ω and 50Ω to ∞Ω respectively. Either range can be selected, although normally 0Ω
to 50Ω is easier to achieve in practice and produces better results. Many papers have been written on this circuit and
should be consulted for the details of design and operation.
Another very similar circuit is a Variable Phase Shifter (illustrated below). The same theory is applied but instead of PIN
diodes (variable RF resistance), the coupler outputs are terminated with varactors. The ideal varactor is a variable
capacitor with the capacitance value changing as a function of the DC bias. Ideally, the magnitude of the reflection
coefficient is 1 for these devices at all bias levels. However, the angle of the reflected signal does change as the
capacitance changes with bias level. So, ideally all of the energy applied to port 1, in the circuit illustrated below, will be
reflected at the varactors and will sum at port 2 (the isolated port of the coupler). However, the phase angle of the signal
will be variable with the DC bias level. In practice, neither the varactors nor the coupler are ideal and both will have
some losses. Again, many papers have been written on this circuit and should be consulted for the details of design and
operation.
Available on Tape
and Reel for Pick and
Place Manufacturing.
USA/Canada:
Toll Free:
Europe:
(315) 432-8909
(800) 411-6596
+44 2392-232392
Model XMC2560E-03
Rev B
Variable Phase Shifter Circuit Utilizing a 3dB Coupler
4
Input
1
Vdc
Output
Γ× 0.707V ∠θ
0.707V∠θ (-3dB)
Varactor Diodes
2
* |Γ (0.5V ∠2θ -90 + 0.5V ∠2θ -90)| =| Γ|
3
0.707V ∠θ -90 (-3dB)
Γ× 0.707V ∠θ -90
* The phase angle of the signal exiting port 2 will vary with the phase angle of Γ, which is the reflection
angle from the varactor. The varactors must be matched so that their reflection coefficients are equal.
USA/Canada:
Toll Free:
Europe:
(315) 432-8909
(800) 411-6596
+44 2392-232392
Available on Tape and
Reel for Pick and Place
Manufacturing.
Model XMC2560E-03
Rev B
Packaging and Ordering Information
Parts are available in both reel and tube. Packaging follows EIA 481-2. Parts are oriented in tape and reel as
shown below. Minimum order quantities are 2000 per reel and 30 per tube. See Model Numbers below for
further ordering information.
XXX XXXX X - XX X
Xinger Coupler
Frequency (MHz)
Size (Inches)
XMC
0405 = 400-500
0825 = 800-2500
0525 = 500-2500
1720 = 1700-2000
2325 = 2300-2500
3338 = 3300-3800
2560 = 2500-6000
A = 0.56 x 0.35
B = 1.00 x 0.50
E = 0.56 x 0.20
L = 0.65 x 0.48
M= 0.40 x 0.20
P = 0.25 x 0.20
Available on Tape
and Reel for Pick and
Place Manufacturing.
Coupling Value
03 = 3dB
05 = 5dB
10 = 10dB
20 = 20dB
30 = 30dB
USA/Canada:
Toll Free:
Europe:
Plating Finish
P = Tin Lead
S = Immersion Tin
(315) 432-8909
(800) 411-6596
+44 2392-232392