©2010-2014 by Murata Electronics N.A., Inc.
RO3118D (R) 4/18/14 Page 1 of 2 www.murata.com
Electrical Characteristics
Characteristic Sym Notes Minimum Typical Maximum Units
Frequency, +25 °C Absolute Frequency fC2, 3, 4, 5 317.925 318.075 MHz
Tolerance from 318.0 MHz fC±75 kHz
Insertion Loss IL 2, 5, 6 1.4 2.0 dB
Quality Factor Unloaded Q QU12900
50Loaded Q QL1800
Temperature Stability Turnover Temperature TO
6, 7, 8
10 25 40 °C
Turnover Frequency fOfC
Frequency Temperature Coefficient FTC 0.032 ppm/°C2
Frequency Aging Absolute Value during the First Year |fA|1, 6 10 ppm/yr
DC Insulation Resistance between Any Two Terminals 5 1.0 M
RF Equivalent RLC Model Motional Resistance RM
5, 7, 9
16
Motional Inductance LM101 µH
Motional Capacitance CM2.4 fF
Shunt Static Capacitance CO5, 6, 9 2.8 pF
Test Fixture Shunt Inductance LTEST 2, 7 86 nH
Lid Symbolization 716 // YWWS
Standard Reel Quantity Reel Size 7 Inch 500 Pieces / Reel
Reel Size 13 Inch 3000 Pieces / Reel
• Ideal for 318 MHz Remote Control and Wireless Security Transmitters
• Very Low Series Resistance
• Quartz Stability
• Complies with Directive 2002/95/EC (RoHS)
The RO3118D is a true one-port, surface-acoustic-wave (SAW) resonator in a surface-mount ceramic case.
It provides reliable, fundamental-mode, quartz frequency stabilization of transmitters and local oscillators
operating at 318 MHz.
Absolute Maximum Ratings
Rating Value Units
Input Power Level 0 dBm
DC Voltage 12 VDC
Storage Temperature -40 to +85 °C
Soldering Temperature (10 seconds / 5 cycles maximum) 260 °C
318.0 MHz
SAW
Resonator
RO3118D
CAUTION: Electrostatic Sensitive Device. Observe precautions for handling.
NOTES:
1. Frequency aging is the change in fC with time and is specified at +65 °C or
less. Aging may exceed the specification for prolonged temperatures
above +65 °C. Typically, aging is greatest the first year after manufacture,
decreasing in subsequent years.
2. The center frequency, fC, is measured at the minimum insertion loss point,
ILMIN, with the resonator in the 50 test system (VSWR 1.2:1). The
shunt inductance, LTEST
, is tuned for parallel resonance with CO at fC.
Typically, fOSCILLATOR or fTRANSMITTER is approximately equal to the
resonator fC.
3. One or more of the following United States patents apply: 4,454,488 and
4,616,197.
4. Typically, equipment utilizing this device requires emissions testing and
government approval, which is the responsibility of the equipment
manufacturer.
5. Unless noted otherwise, case temperature TC= +25 ± 2 °C.
6. The design, manufacturing process, and specifications of this device are
subject to change without notice.
7. Derived mathematically from one or more of the following directly
measured parameters: fC, IL, 3 dB bandwidth, fC versus TC, and CO.
8. Turnover temperature, TO, is the temperature of maximum (or turnover)
frequency, fO. The nominal frequency at any case temperature, TC, may be
calculated from: f = fO[1 - FTC (TO-TC)2]. Typically oscillator TO is
approximately equal to the specified resonator TO.
9. This equivalent RLC model approximates resonator performance near the
resonant frequency and is provided for reference only. The capacitance CO
is the static (nonmotional) capacitance between the two terminals
measured at low frequency (10 MHz) with a capacitance meter. The
measurement includes parasitic capacitance with "NC” pads unconnected.
Case parasitic capacitance is approximately 0.05 pF. Transducer parallel
capacitance can by calculated as: CPCO-0.05pF.
SM3838-6 Case
3.8 X 3.8
Pb
Copyright © Murata Manufacturing Co., Ltd. All Rights Reserved 2007
©2010-2014 by Murata Electronics N.A., Inc.
RO3118D (R) 4/18/14 Page 2 of 2 www.murata.com
-80-60-40-20 0+20 +40 +60
0
-50
-100
-150
+80
-200
0
-50
-100
-150
-200
f
C
= f
O
, T
C
= T
O
T = T
C
- T
O
( °C )
(f-foo
)/f(ppm)
0.05 pF*
0.05 pF
Cp
Co+
=
*Case Parasitics
Cp
Rm Lm C m
Equivalent RLC Model
Temperature Characteristics
The curve shown on the right accounts for resonator contribution only and
does not include LC component temperature contributions.
Pin Connection
1NC
2 Terminal
3NC
4NC
5NC
6 Terminal
7NC
8NC
Electrical Connections
The SAW resonator is bidirectional and
may be installed with either orientation.
The two terminals are interchangeable
and unnumbered. The callout NC
indicates no internal connection. The NC
pads assist with mechanical positioning
and stability. External grounding of the NC
pads is recommended to help reduce
parasitic capacitance in the circuit.
Example Application Circuits
Parameter Test Circuit
Power Test Circuit
+VDC
ROXXXXC
Bottom View
200k
C1
L1
+VDC
C2
RF Bypass
Typical Local Oscillator Application Output
2 3
6 5 4
1
Modulation
Input
ROXXXXC
Bottom View
200k
C1
L1
(Antenna)
47
+9VDC
C2
RF Bypass
470
Typical Low-Power Transmitter Application
2 3
6 5 4
1
Low-Loss
Matching
Network to
50
50 Source
at F C
PINCIDENT
PREFLECTED
2 3
6 5 4
1
From 50
Network Analyzer
To 50
Network Analyzer
2
3
6
5
4
1
1
2
3
6
5
4
1
2
3
6
5
4
A
BC
DJ
E
GH
I
Case Dimensions
Dimension mm Inches
Min Nom Max Min Nom Max
A3.60 3.80 4.00 0.142 0.150 0.157
B3.60 3.80 4.00 0.142 0.150 0.157
C1.10 1.30 1.50 0.043 0.050 0.060
D0.95 1.10 1.25 0.037 0.043 0.049
E2.39 2.54 2.69 0.094 0.100 0.106
G0.90 1.00 1.10 0.035 0.040 0.043
H1.90 2.00 2.10 0.748 0.079 0.083
I0.50 0.60 0.70 0.020 0.024 0.028
J1.70 1.80 1.90 0.067 0.071 0.075
Copyright © Murata Manufacturing Co., Ltd. All Rights Reserved 2007
