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RF Monolithics, Inc.
RFM Europe
1999 by RF Monolithics, Inc. The stylized RFM logo are registered trademarks of RF Monolithics, Inc.
Phone: (972) 233-2903
Phone: 44 1963 251383
Fax: (972) 387-9148
Fax: 44 1963 251510
E-mail: info@rfm.com
http://www.rfm.com
RO2171-031301
Page 1 of 2
Electrical Characteristics
Characteristic
Absolute Frequency
Tolerance from 310.075 MHz
Sym
f
C
f
C
IL
Q
U
Q
L
T
O
f
O
FTC
|f
A
|
Notes
Minimum
310.025
Typical
Maximum
310.125
±50
5.0
Units
MHz
kHz
Center Frequency (+25 °C)
2, 3, 4, 5
Insertion Loss
Quality Factor
2, 5, 6
3.1
dB
Unloaded Q
50
Loaded Q
Turnover Temperature
Turnover Frequency
Frequency Temperature Coefficient
Absolute Value during the First Year
5, 6, 7
11,800
3,500
52
f
c
+ 8.4
0.037
≤10
Temperature Stability
6, 7, 8
37
67
°C
kHz
ppm/°C
2
ppm/yr
M
μH
Frequency Aging
DC Insulation Resistance between Any Two Pins
RF Equivalent RLC Model
1
5
1.0
Motional Resistance
Motional Inductance
Motional Capacitance
Pin 1 to Pin 2 Static Capacitance
Transducer Static Capacitance
R
M
L
M
C
M
C
O
C
P
L
TEST
5, 7, 9
43
78
260.257
1.01245
2.5
2.2
105
fF
pF
pF
5, 6, 9
5, 6, 7, 9
2, 7
2.2
2.8
Test Fixture Shunt Inductance
Lid Symbolization (in Addition to Lot and/or Date Codes)
nH
RFM RO2171
TO39-3 Case
Ideal for 310.075 MHz Transmitters
Low Series Resistance
Quartz Stability
Rugged, Hermetic, Low-Profile TO39 Case
The RO2171 is a true one-port, surface-acoustic-wave (SAW) resonator in a low-profile TO39 case. It pro-
vides reliable, fundamental-mode, quartz frequency stabilization of fixed-frequency transmitters operating at
310.075 MHz. The RO2171 is designed specifically for AM transmitters used in automotive-keyless-entry
applications operating in the USA under FCC Part 15, in Canada under DoC RSS-210, and in Italy.
Absolute Maximum Ratings
Rating
Value
+0
±30
-40 to +85
Units
dBm
VDC
°C
CW RF Power Dissipation
DC Voltage Between Any Two Pins
Case Temperature
310.075 MHz
SAW
Resonator
RO2171
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 temperatures above +65°C.
Typically, aging is greatest the first year after manufacture, decreasing signifi-
cantly in subsequent years.
The center frequency, f
C
, is measured at the minimum insertion loss point, IL
MIN
,
with the resonator in the 50
test system (VSWR
≤
1.2:1). The shunt induc-
tance, L
TEST
, is tuned for parallel resonance with C
O
at f
C
. Typically, f
OSCILLA-
TOR
or f
TRANSMITTER
is less than the resonator f
C
.
One or more of the following United States patents apply: 4,454,488 and
4,616,197 and others pending.
Typically, equipment designs utilizing this device require emissions testing and
government approval, which is the responsibility of the equipment manufacturer.
Unless noted otherwise, case temperature T
C
= +25°C±2°C.
The design, manufacturing process, and specifications of this device are subject
to change without notice.
2.
3.
4.
5.
6.
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
.
Turnover temperature, T
O
, is the temperature of maximum (or turnover) fre-
quency, f
O
. The nominal frequency at any case temperature, T
C
, may be calcu-
lated from: f = f
O
[1 - FTC (T
O
-T
C
)
2
]. Typically,
oscillator
T
O
is 20°C less than
the specified
resonator
T
O
.
This equivalent RLC model approximates resonator performance near the reso-
nant frequency and is provided for reference only. The capacitance C
O
is the
static (nonmotional) capacitance between pin1 and pin 2 measured at low fre-
quency (10 MHz) with a capacitance meter. The measurement includes case
parasitic capacitance with a floating case. For usual grounded case applica-
tions (with ground connected to either pin 1 or pin 2 and to the case), add
approximately 0.25 pF to C
O
.
8.
9.