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Electronic Symbols.doc
Revision 14
Last modified July 26, 2008
You wouldn’t believe how many engineers download this free Word file each month!
This Word document contains some schematic symbols for use in Microsoft Word, PowerPoint
and Excel files for reports and presentations. If you happen to have Agilent ADS or AutoCAD,
you may find these tools more convenient for creating schematics. If you are a microwave
cheapskate, you may have created these symbols yourself a hundred times. Using this
downloadable file, now you won’t have to!
Did you find some useful schematic symbol(s) missing? Drop a line to
techwriter@microwaves101.com and we’ll see if we can add it!
The Microsoft Word Drawings are pasted into tables to keep them “anchored” within the text.
Just double-click on a figure to edit it. When you are editing a figure, remember that everything
started out on a 0.05 inch grid. You may have to turn off the grid snap to get things to align
properly.
Around the pictures (inside the Microsoft Word Drawings) are invisible boxes with clear filling.
These are used to define the outside edges of the pictures.
Microsoft software does some peculiar things if you try to scale the pictures. We recommend
that if your picture is too big, you should work on decreasing the size of the elements inside the
picture rather than squeezing the entire picture down to size. Once you shrink any of the
schematic elements, all bets are off as to whether they will look aligned when you connect them
up.
It is very simple to copy from one picture to another. You need to double-click the picture you
are copying from, then click and control C the element you want to copy, then exit the picture,
click into the second picture and hit control V.
Good luck!
Microwaves101.com
Jumpers and
Capacitors dots
Ground
symbols
Inductors Resistors
Resistors, capacitors and inductors
MESFET MOSFETs
NMOS PMOS
Send us some more
symbols please!
FETS and transistors
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Pi attenuator
Circulators and isolators
Tee attenuator
Attenuators, circulators and isolators
RF
IF
LO
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RF
IF
LO
Double-balanced mixers
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Inside only Outside only Inside/outside
DC Blocks
RF only RF & DC RF IF
LO
Bias tee
DC only
Mixer
Diodes
Zener
Variable Phase
attenuator shifter
Diodes, DC blocks, mixer, phase shifter/attenuator
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HPF
F
BPF
LPF
BSF
Filters
SPDT SP3T SPST
Switches
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Single box hybrid
0.707 Z0
Vin 0.707 Vin<-90
(port 1) (port 2)
Z0 Z0
0.707 Vin<180
isolated port (port 3)
(port 4) 0.707 Z0
all arms are λ/4
in length
Double box hybrid
Z0 Z0
Vin 0.707 Vin<180
(port 1) (port 2)
2.414 Z0 1.414 Z0 2.414 Z0
0.707 Vin<-90
isolated port Z0 Z0 (port 3)
(port 4)
all arms are λ/4
in length
Unequal-split hybrid power divider
Z0A
VIN PA
(port 1) (port 2)
Z0B Z0B
PB
isolated port Z0A (port 3)
(port 4)
all arms are λ/4
in length
Branchline hybrid couplers
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Ζ0Α, 3λ/4
PIN PB
Ζ0Β, λ/4 Ζ0Β, λ/4
PA Ζ0Α, λ/4
isolated port
Unequal split rat race coupler
1.414 Ζ0, 3λ/4
Vin 0.707 Vin<90
(port 1) (port 2)
1.414 Ζ0, 1.414 Ζ0,
λ/4 λ/4
1.414 Ζ0, isolated port
0.707 Vin<-90 λ/4 (port 3)
(port 4)
Equal-split rat race coupler
Rat race coupler
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2 Z0, λ/4 Port 2
Port 1
2Z0
2 Z0, λ/4 Port 3
Basic 3 dB Wilkinson splitter
Port 2
λ/4 (50 Ω)
Port 1
(50 Ω) 59.4 Ω
100Ω
λ/4 59.4Ω
42Ω λ/4 Port 3
(50 Ω)
Wilkinson with input transformer (Z0=50Ω)
λ/4
Port 2
λ/4 (50 Ω)
Port 1 56.3 Ω
(50 Ω) 66.0 Ω
93.7 Ω 155.5 Ω
λ/4 66.6 Ω
39.8Ω 56.3 Ω
λ/4 Port 3
λ/4 (50 Ω)
Two stage Wilkinson with input transformer
λ/4
λ/4 PA
Z0C (port 2)
Z0Α
PIN RW
(port 1) Ζ0Β
Z0D
λ/4 PB
λ/4 (port 3)
Unequal split Wilkinson power divider
Wilkinson power splitters
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N-section Wilkinson
ZN-1 Z2 Z1
ZN Port 2
Port 1
RN RN-1 R2 R1
ZN
ZN-1 Z2 Z1
Port 3
N-section Wilkinson - odd mode
Port 2
ZN ZN-1 Z2 Z1
Zin,odd
ρodd
0 ohms 0.5xRN 0.5xRN-1 0.5xR2 0.5xR1
N-section Wilkinson - even mode
Port 2
ZN ZN-1 Z2 Z1
Zin,even
ρodd
2xZ0
N-section Wilkinson, Even/odd modes
Microwaves101.com
λ/4 Port 2
Port 2
Port 1
Port 1
λ/4 Port 3
Port 3
Series SPDT switch
Shunt SPDT switch
λ/4
Port 2 Port 2
Port 1 Port 1
λ/4
Port 3 Port 3
Series-shunt SPDT switch Series-shunt-shunt SPDT switch
λ/4
λ/4 Port 2
Port 1
λ/4
λ/4 Port 3
Shunt-shunt SPDT
switch
Switch configurations
Microwaves101.com
3 Z0, λ/4 Port 2
Z0
Port 1 Port 3
3 Z0, λ/4
Z0
3 Z0, λ/4 Z0
Port 4
Three-way Wilkinson splitter, star resistors
3 Z0, λ/4 Port 2
Port 1 3Z0 Port 3
3 Z0, λ/4
3Z0
3 Z0, λ/4 3Z0
Port 4
Three-way Wilkinson splitter, delta resistors
Three-way Wilkinsons
Z0/3 Port 2
Z0/3
Port 1
Z0/3 Port 3
Y-type 6 dB resistive splitter
Z0 Port 2
Port 1 Z0
Z0 Port 3
Delta-type 6 dB resistive splitter
Resistive splitters
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R1
Z1 R2 Z2
L-pad matching network (Z1>Z2)
L-Pad
R1
Port 2
R2 Z0
Port 1
Z0
R3
Port 3
R4 Z0
Owen resistive splitter
Microwaves101.com
0.707 Vin<-90
(port 2) isolated port
all arms are λ/4 Z3 (port 4)
in length
R=Z0
Z2 Z4
Z1
Vin
(port 1)
Z2 Z4
R=Z0
Z3
isolated port
(port 5)
Equal-split Gysel 0.707 Vin<-90
(port 3)
Gysel power splitter
Detector
diode
Video
RF Input
out
In matching
network RF Bypass
choke cap
Basic
detector
Detector circuits
Microwaves101.com
+ - + - + - + -
Cell Multiple cells (as
Battery
in a flashlight)
+ - + - + -
Multiple
batteries (ganged
for more current)
Multiple batteries (ganged for more voltage)
+ -
+ -
Meters, power supplies and batteries
Series
Parallel
resonance
resonance
L C
C L R
R
Resonant circuits
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G
MOSFETs and Drivers
N-channel
Logic
AND NAND
G
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Mixer
IF pad
RF RF
IF
Input
output
LO
LNA IF amp
LO
Input
Receivers
Microwave Capacitor model
C LS ESR
CP
Capacitor model
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Current
source
Lossless transmission
line model
General transmission line model
DC AC
Voltage Voltage L' R' L'
source source
C' G' C'
+
-
Voltage and current sources, transmission line model
Four-terminal Ohmic
Capacitive switch Three-terminal Ohmic switch switch
VA
VA
VA1 VA2
MEMS switches
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Input Coupled Input
port port port
Isolated Direct Output
port port port
Balanced amp
Lange couplers. balanced amp
