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Electrical Characteristics
Characteristic Sym Notes Minimum Typical Maximum Units
Center Frequency, +25 °C Absolute Frequency fC2,3,4,5 433.845 433.995 MHz
Tolerance from 433.920 MHz ∆fC±75 kHz
Insertion Loss IL 2,5,6 1.5 2.2 dB
Quality Factor Unloaded Q QU5,6,7 14200
50 Ω Loaded Q QL2200
Temperature Stability Turnover Temperature TO6,7,8 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≤10 ppm/yr
DC Insulation Resistance between Any Two Terminals 5 1.0 MΩ
RF Equivalent RLC Model Motional Resistance RM5, 7, 9 18.46 Ω
Motional Inductance LM96.6 µH
Motional Capacitance CM1.39 fF
Shunt Static Capacitance CO5, 6, 9 1.82 pF
Test Fixture Shunt Inductance LTEST 2, 7 74.1 nH
Lid Symbolization (in addition to Lot and/or Date Codes) 807 // YWWS
• Ideal for European 433.92 MHz Transmitters
• Very Low Series Resistance
• Quartz Stability
• Surface-Mount Ceramic Case
• Complies with Directive 2002/95/EC (RoHS)
The RO3101A-21 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 433.92 MHz. This SAW is designed specifically for remote-control and wireless security
transmitters operating in Europe under ETSI I-ETS 300 220.
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 maximum) 260 °C
433.92 MHz
SAW
Resonator
RO3101A-21
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 specificat ion for prolonged temperatures
above +65 °C. Typically, aging is greatest the first year after manufacture,
decreasing in subsequent years.
2. The cen ter frequency, fC, is measured at t he minimum insertion loss point,
ILMIN, with the resonator in the 50 Ω test system (VSWR ≤ 1.2:1). The
shunt inductance, LTEST, is tuned for parallel resonance with CO at fC.
Typica lly, fOSCILLATOR or fTRANSMITTER is approx imately equal to the
resonator fC.
3. One or more of the following Unit ed States patents apply: 4,454,488 and
4,616,197.
4. Typically, equipment utilizing this devic e requires emissions testing and
government approval, which is the respons ibility of the equipment
manufacturer.
5. Unless noted ot herwise, 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 direc tly
measured parameters: fC, IL, 3 dB bandwidth, fC versus TC, and CO.
8. Turnover temperature, TO, is the temperature of maxi mum (or turnover)
frequenc y, fO. The nomina l frequ ency at any case te mperatu re, TC, ma y be
calculated from: f = fO[1 - FTC (TO-TC)2]. Typically oscillator TO is
approximately equal t o the specifie d resonator TO.
9. This equival ent RLC model approximates reso nator performance near t he
resonant frequenc y and is pro vided fo r refere nce only. The capac itanc e CO
is the static (nonmotional) capacitanc e between the tw o terminals
measured at low frequency (10 MHz) with a capacitance meter. The
measuremen t includes p arasitic cap acitanc e with "NC” pads unco nnected.
Case parasitic capacitance is app roximately 0.05 pF. Transducer parallel
capacitance ca n by cal cu l ated as: CP≈CO-0.05pF.
10. Tape and Reel standard per ANSI / EIA 481.
SM5035-4
Pb
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©2008-2011 by RF Monolithics, Inc. RO31 01A-21 6/28/11
Electrical Connections
The SAW resonator is bidirectional and may be
installed with either orientation. T he 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.
Typical Test Circuit
The test circuit inductor , LTEST, is tuned to resonate with the static
capacitance, CO, a t FC.
Typical Application Circuits
Equivalent Model
Temperature Characteristics
The curve shown on the right
accounts for resonator
contribution only and does not
include LC component
temperature contributions.
Case
Terminal
Terminal
Case Ground
Case Ground
ELECTRICAL TEST
From 50 Ω
Network Analyzer To 50 Ω
Networ k A nalyzer
50 Ω Source
at FCREFLECTED
INCIDENT
P
P
Low-Loss
Matching
Network to
50 Ω
Terminal
Terminal
NC NC
POWE R T EST
CW RF Power Dissipation = INCIDENT - REFLECTED
P P
C1
C2
L1
(Antenna)
+9VDC
47
RF Bypass
Modulation
Input
Typical Low-Power Transmitter Application
RO3XXXA
Bottom View 470
200kΩ
C1
C2
L1
Output
+VDC
RF Bypass
+VDC
Typical Local Oscillator Applications
RO3XXXA
Bottom View
Dimensions Millimeters Inches
Min Nom Max Min Nom Max
A 4.87 5.00 5.13 0.191 0.196 0.201
B 3.37 3.50 3.63 0.132 0.137 0.142
C 1.45 1.53 1.60 0.057 0.060 0.062
D 1.35 1.43 1.50 0.040 0.057 0.059
E 0.67 0.80 0.93 0.026 0.031 0.036
F 0.37 0.50 0.63 0.014 0.019 0.024
G 1.07 1.20 1.33 0.042 0.047 0.052
H - 1.04 - - 0.041 -
I - 1.46 - - 0.058 -
J - 0.50 - - 0.019 -
K - 1.05 - - 0.041 -
L - 1.44 - - 0.057 -
M - 0.71 - - 0.028 -
0.05 pF*
0.05 pF
Cp
Co+
=
*Case Parasitics
Cp
Rm
Lm C m
-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)
A
B C
D
E ( 3 x )
F ( 4 x )
G ( 1 x )
T o p V i e w S i d e V i e w B o t t o m V i e w
1
2
3
4
H
I
H H
J
J
K
L
MM
PCB Land Pattern
Top View
