鈥?/div>
Ideal Front-End Filter for European Wireless Receivers
Low-Loss, Coupled-Resonator Quartz Design
Simple External Impedance Matching
Rugged TO39 Hermetic Package
The RF1254 is a low-loss, compact, and economical surface-acoustic-wave (SAW) filter designed to provide
front-end selectivity in 952.775 MHz receivers. Typical applications of these receivers are wireless remote-
control and security devices operating in Europe under ETSI I-ETS 300 220, in Germany under FTZ 17 TR
2100, in the United Kingdom under DTI MPT 1340 (for automotive only), in France under PTT Specifications
ST/PAA/TPA/AGH/1542, and in Scandinavia.
RFM鈥檚 advanced SAW design and fabrication technology is utilized to achieve high performance and very low
loss with simple external impedance matching (not included). Quartz construction provides execellent fre-
quency stablility over a wide temperature range.
952.775 MHz
SAW Filter
TO39-3 Case
Electrical Characteristics
Characteristic
Center Frequency at 25擄C
Absolute Frequency
Tolerance from 433.92 MHz
Insertion Loss
3 dB Bandwidth
Rejection
at f
C
- 21.4 MHz (Image)
at f
C
- 10.7 MHz (LO)
Ultimate
Temperature
Operating Case Temp.
Turnover Temperature
Turnover Frequency
Freq. Temp. Coefficient
Frequency Aging
External Impedance
Absolute Value during the First Year
Series Inductance
Shunt Capacitance
Lid Symbolizaation (in addition to Lot and/or Date Codes)
T
C
T
O
f
O
FTC
|fA|
L1
L2
C1
C2
2, 7
1
4, 7, 8
-35
20
25
f
C
0.032
<鹵10
4.8
4.8
8
8.3
RFM RF1254
pF
2
Sym
f
C
鈭唂
C
IL
BW
3
Notes
2, 3, 4, 5, 6
2, 4, 7
2, 3, 4, 7
1250
35
15
50
30
80
Minimum
952.675
Typical
952.775
鹵100
3
Maximum
952.875
5.0
1550
Units
MHz
kHz
dB
kHz
dB
+85
30
擄C
擄C
MHz
ppm/擄C
2
ppm/yr
nH
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擄C or less. Aging may exceed the specification for prolonged temperatures
above +65擄C. Typically, aging is greatest the first year after manufacture, decreasing significantly in subsequent years.
2. Unless noted otherwise, all measurements are made with the filter installed in the specified test fixture, which is connected to a 50鈩?test system with
VSWR
鈮?/div>
1.2:1. The test fixture鈥檚 L and C are adjusted for minimum insertion loss at the filter center frequency, f
C
. Note that insertion loss, bandwidth,
and passband shape are dependent on the impedance matching component values and quality. The optimum impedance matching component val-
ues are dependent on circuit parasitic losses.
3. The frequency f
C
is defined as the midpoint between the 3dB frequencies.
4. Unless noted otherwise, specifications apply over the entire specified operating temperature range.
5. One or more of the following U.S. Patents apply: 4,454,488; 4,616,197; and others pending.
6. All equipment designs utilizing this product must be approved by the appropriate government agency prior to manufacture or sale.
7. The design, manufacturing process, and specifications of this device are subject to change without notice.
8. The turnover temperature, T
O
, is the temperature of maximum (or turnover) frequency, f
O
. The nominal center frequency at any case temperature,
TC, may be calculated from: f=f
O
[1-FTC (T
O
-T
C
)2].
RF Monolithics, Inc.
Phone: (972) 233-2903
Fax: (972) 387-9148
RFM Europe
Phone: 44 1963 251383
Fax: 44 1963 251510
漏1999 by RF Monolithics, Inc. The stylized RFM logo are registered trademarks of RF Monolithics, Inc.
E-mail: info@rfm.com
http://www.rfm.com
RF1254-110800
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