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©2008 by RF Monolithics, Inc. RO2103A - 3/24/08
Electrical Characteristics
Characteristic Sym Notes Minimum Typical Maximum Units
Frequency (+25 °C) Nominal Frequency
f
C
2, 3, 4, 5
417.925 418.075 MHz
Tolerance from 418.000 MHz
Δf
C
±75 kHz
Insertion Loss IL 2, 5, 6 1.0 2.0 dB
Quality Factor Unloaded Q
Q
U
5, 6, 7
16,100
50 Ω Loaded Q
Q
L
1,700
Temperature Stability Turnover Temperature
T
O
6, 7, 8
10 25 40 °C
Turnover Frequency
f
O
f
C
Frequency Temperature Coefficient FTC 0.032
ppm/°C
2
Frequency Aging Absolute Value during the First Year
|f
A
|
1, 6 10 ppm/yr
DC Insulation Resistance between Any Two Terminals 5 1.0 MΩ
RF Equivalent RLC Model Motional Resistance
R
M
5, 6, 7, 9
12 26 Ω
Motional Inductance
L
M
74.8223 µH
Motional Capacitance
C
M
1.93705 fF
Transducer Static Capacitance
C
O
5, 6, 9 1.6 1.9 2.2 pF
Test Fixture Shunt Inductance
L
TEST
2, 7 80 nH
Lid Symbolization 106
• Ideal for 418 MHz Transmitters in the U.K. and U.S.
• Very Low Series Resistance
• Quartz Stability
• Surface-Mount, Ceramic Case with 21 mm
2
Footprint
• Complies with Directive 2002/95/EC (RoHS)
The RO2103A 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 fixed-frequency transmitters
operating at 418.0 MHz. This SAW is designed for remote-control and wireless security transmitters operating
in the United Kingdom under DTI MPT 1340 and in the USA under FCC Part 15.
Absolute Maximum Ratings
Rating Value Units
CW RF Power Dissipation (See Typical Test Circuit) +0 dBm
DC Voltage Between Terminals (Observe ESD Precautions) ±30 VDC
Case Temperature -40 to +85 °C
Soldering Temperature (10 seconds / 5 cycles max.) 260 °C
418.0 MHz
SAW
Resonator
RO2103A
CAUTION: Electrostatic Sensitive Device. Observe precautions for handling.
Notes:
1. Frequency aging is the change in f
C
with time and is specified at
+65°C or less. Aging may exceed the specification for prolonged tem-
peratures above +65°C. Typically, aging is greatest the first year after
manufacture, decreasing in subsequent years.
2. The center frequency, f
C
, is measured at the minimum insertion loss
point, IL
MIN
, with the resonator in the 50 Ω test system (VSWR ≤
1.2:1). The shunt inductance, L
TEST
, is tuned for parallel resonance
with C
O
at f
C
. Typically, f
OSCILLATOR
or f
TRANSMITTER
is approximately
equal to the resonator f
C
.
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 T
C
=+25°C±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: f
C
, IL, 3 dB bandwidth, f
C
versus T
C
, and C
O
.
8. Turnover temperature, T
O
, is the temperature of maximum (or
turnover) frequency, f
O
. The nominal frequency at any case
temperature, T
C
, may be calculated from: f = f
O
[1 - FTC (T
O
-T
C
)
2
].
Typically oscillator T
O
is approximately equal to the specified
resonator T
O
.
9. This equivalent RLC model approximates resonator performance near
the resonant frequency and is provided for reference only. The
capacitance C
O
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:
C
P
≈ C
O
-0.05pF.
SM-2 Case
