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©2008 by RF Monolithics, Inc. RO3112 - 3/26/08
Electrical Characteristics
Characteristic Sym Notes Minimum Typical Maximum Units
Center Frequency (+25 °C) Absolute Frequency fC2, 3, 4, 5 433.345 433.495 MHz
Tolerance from 433.420 MHz ΔfC±75 kHz
Insertion Loss IL 2, 5, 6 1.3 1.5 dB
Quality Factor Unloaded Q QU5, 6, 7 7500
50 Ω Loaded Q QL940
Temperature Stability Turnover Temperature TO6, 7, 8
10 25 40 °C
Turnover Frequency fOfckHz
Frequency Temperature Coefficient FTC 0.037 ppm/°C2
Frequency Aging Absolute Value during the First Year |fA|1≤10 ppm/yr
DC Insulation Resistance between Any Two Pins 5 1.0 MΩ
RF Equivalent RLC Model Mot ional Resistance RM5, 7, 9
14.5 Ω
Motional Inductance LM39.6 µH
Motional Capacitance CM3.4 fF
Pin 1 to Pin 2 Static Capacitance CO5, 6, 9 3.5 pF
Trans ducer Static Capacitance CP5, 6, 7, 9 3.2 pF
Test Fixture Shunt Inductance LTEST 2, 7 39 nH
Lid Symbolization (in Addition to Lot and/or Date Codes) RFM RO3112
TO39-3 Case
• Ideal for European 433.92 MHz Superhet Receiver LOs
• Very Low Series Resistance
• Quartz Stability
• Rugged, Hermetic, Low-Profile TO39 Case
• Complies with Directive 2002/95/EC (RoHS)
The RO31 12 is a true one-port, surface-acoustic-wave (SAW) resonator in a low-profile TO39 case. It provides
reliable, fundamental-mode, quartz frequency stabilization of local oscillators operating at approximately
433.42 MHz. The RO2112 is designed for IC based 433.92 MHz superhet receivers with 500 kHz IF (Philips
UAA3201T). Applications include remote-control and wireless sec urity devices operating in Europe under
ETSI I-ETS 300 220 and in Germany under FTZ 17 TR 2100.
Absolute Maximum Ratings
Rating Value Units
CW RF Power Dissipation (See: Typical Test Circ uit) +0 dBm
DC Voltage Between Any Two Pins (Observe ESD Precautions) ±30 VDC
Case Temperature -40 to +85 °C
Soldering Temperature (10 seconds / 5 cycles max.) 260 °C
433.42 MHz
SAW
Resonator
RO3112
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 significantly in subsequent years.
2. The center frequency, fC, is measured at the minimum insertion loss point,
ILMIN, with the res onator in the 50 Ω test system (VSWR ≤ 1.2: 1). The
shunt inductance, LTEST, is tuned for parallel resonance with CO at fC.
Typi cally, fOSCILLATOR or fTRANSMITTER is less than the resonator fC.
3. One or more of the following United Sta tes patents apply: 4,454,488 and
4,616,197 and others pending.
4. Typically, equipment designs utilizing this device require emissions testing
and government approval, which is the responsibility of the equipment
manufacturer.
5. Unless noted otherwis e, case temperature TC= +25°C±2°C.
6. The design, manufacturing process, and sp ecifications of this dev ice are
subject to change without no tice.
7. Derived mat hematically 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 temperatur e of maximum (or turnover)
frequenc y, fO. The nomina l frequenc y at an y case te mperature, TC, may be
calculated from: f = fO[1 - FTC (TO-TC)2]. Typically, oscillator TO is 20°C
less than the specified resonator TO.
9. This equiv alent RLC model approximates resonator performance near the
resonan t frequen cy and is provided for refer ence o nly. The capaci tanc e CO
is the static (nonmotional) capacitance between pin1 and pin 2 measured
at low frequency (10 MHz) with a capacitance meter. The measureme nt
includes case p arasitic capacitance with a floating case. For usual
ground ed case applications (wit h ground connected to either pin 1 or pin 2
and to the case), add approximately 0.25 pF to CO.
Pb
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©2008 by RF Monolithics, Inc. RO3112 - 3/26/08
Electrical Connections
This one-port, two-terminal SAW resonator is bidirectional. The terminals
are interchangeable with the exception of circuit board layout.
Typical Test Circuit
The test circuit inductor, LTEST, is tuned to resonate with the st atic
capacitance, CO at FC.
Typical Application Circuits
Temperature Characteristics
Equivalent LC Model
The following equivalent LC model is valid near resonance:
Case Design
Pin Connection
1 Terminal 1
2 Terminal 2
3 Case Ground
Network
Analyzer Network
Analyzer
Electri cal Test:
12
3
ΩΩ
50
Ω
Source at
F
C
Low-Loss
Matching
Network
50
Ω
to
Pow er Test:
P
P
INCIDENT
INCIDENT
CW RF Po wer Dissi pation = -
REFLECTED
REFLECTED
P
P
3
2
MPS-H10
+9VDC
47
RF Bypass
L1
C1
C2
200k
Ω
Modulation
Input
ROXXXX
Botto m V iew
470
Typ i cal Low-Pow er Tran s m itt er A pp li cation:
1
2
3
(Antenna)
+VDC
RF Bypass
L1
C2
ROXXXX
Bottom View
Typical Local Oscillator Application:
12
3
Output
+VDC
C1
Dimensions Millimeters Inches
Min Max Min Max
A 9.40 0.370
B 3.18 0.125
C 2.50 3.50 0.098 0.138
D 0.46 Nominal 0.018 Nominal
E 5.08 Nominal 0.200 Nominal
F 2.54 Nominal 0.100 Nominal
G 2.54 Nominal 0.100 Nominal
H 1.02 0.040
J1.40 0.055
The curve shown on the right
accounts for resonator
contribution only and does not
include oscillator temperature
characteristics.
-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
Δ
T = T
C
- T
O
( °C )
(f-foo
)/f(ppm)
0.5 p F*
0.25 pF*
Cp
Co=+
*Case Parasitics
R
L
C
0.5 pF*
Cp
1
2
3
MMM
B
45°
J
(2 places)
D
(3 places)
H
G
EF
C
A
Bot to m View
Pin 1 Pin 2
Pin 3