RO2125 • • • • Ideal for 315 MHz LO in Superhet Receivers with 10.7 MHz IF Very Low Series Resistance Quartz Stability Rugged, Hermetic, Low-Profile TO39 Case 304.3 MHz SAW Resonator The RO2125 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 304.3 MHz. This SAW is designed for 315 MHz superhet receivers with 10.7 MHz IF (Philips UAA3201T). Applications include automotive-keyless-entry receivers operating in the USA under FCC Part 15, in Canada under DoC RSS-210, and in Italy. Absolute Maximum Ratings Rating Value Units +0 dBm ±30 VDC -40 to +85 °C CW RF Power Dissipation (See: Typical Test Circuit) DC Voltage Between Any Two Pins (Observe ESD Precautions) Case Temperature TO39-3 Case Electrical Characteristics Characteristic Center Frequency (+25 °C) Absolute Frequency Sym fC Tolerance from 304.300 MHz ∆fC 2, 3, 4, 5 IL 2, 5, 6 Unloaded Q QU 50 Ω Loaded Q QL Turnover Temperature TO Insertion Loss Quality Factor Temperature Stability Turnover Frequency Frequency Aging Notes FTC Absolute Value during the First Year |fA| 0.9 Maximum 304.375 Units MHz ±75 kHz 1.5 dB 40 °C 2,000 10 25 fc 6, 7, 8 0.037 5 ppm/°C2 ppm/yr ≤10 1 DC Insulation Resistance between Any Two Pins RF Equivalent RLC Model Typical 18,300 5, 6, 7 fO Frequency Temperature Coefficient Minimum 304.225 1.0 MΩ RM Motional Inductance LM Motional Capacitance CM Pin 1 to Pin 2 Static Capacitance CO 5, 6, 9 CP 5, 6, 7, 9 2.9 pF LTEST 2, 7 84 nH Transducer Static Capacitance Test Fixture Shunt Inductance 10 19 Ω Motional Resistance 95.7126 5, 7, 9 µH 2.85803 2.9 Lid Symbolization (in Addition to Lot and/or Date Code) 3.2 fF 3.5 pF RFM RO2125 CAUTION: Electrostatic Sensitive Device. Observe precautions for handling. Notes: 1. 2. 3. 4. 5. 6. 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. The center frequency, fC, is measured at the 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. Typically, fOSCILLATOR or fTRANSMITTER is less than the resonator fC. 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 TC = +25°C±2°C. The design, manufacturing process, and specifications of this device are subject to change without notice. 7. 8. 9. Derived mathematically from one or more of the following directly measured parameters: fC, IL, 3 dB bandwidth, fC versus TC, and CO. Turnover temperature, TO, is the temperature of maximum (or turnover) frequency, fO. The nominal frequency at any case temperature, TC, may be calculated from: f = fO [1 - FTC (TO -TC)2]. Typically, oscillator TO is 20°C less than the specified resonator TO. This equivalent RLC model approximates resonator performance near the resonant frequency and is provided for reference only. The capacitance CO is the static (nonmotional) capacitance between pin1 and pin 2 measured at low frequency (10 MHz) with a capacitance meter. The measurement includes case parasitic capacitance with a floating case. For usual grounded case applications (with ground connected to either pin 1 or pin 2 and to the case), add approximately 0.25 pF to CO. RF Monolithics, Inc. Phone: (972) 233-2903 Fax: (972) 387-9148 RFM Europe Phone: 44 1963 251383 Fax: 44 1963 251510 ©1999 by RF Monolithics, Inc. The stylized RFM logo are registered trademarks of RF Monolithics, Inc. E-mail: [email protected] http://www.rfm.com RO2125-102699 Page 1 of 2 304.3 MHz SAW Resonator Electrical Connections Temperature Characteristics Pin Connection 1 Terminal 1 2 Terminal 2 3 Case Ground Bottom View Pin 1 Pin 2 The curve shown on the right accounts for resonator contribution only and does not include oscillator temperature characteristics. fC = f O , T C = T O 0 0 -50 -50 -100 -100 -150 -150 (f-fo ) / fo (ppm) This one-port, two-terminal SAW resonator is bidirectional. The terminals are interchangeable with the exception of circuit board layout. -200 -80 -60 -40 -20 Pin 3 -200 0 +20 +40 +60 +80 ∆T = TC - T O ( °C ) Typical Test Circuit The test circuit inductor, LTEST, is tuned to resonate with the static capacitance, CO at FC. Equivalent LC Model Electrical Test: The following equivalent LC model is valid near resonance: Ω 1 Ω 2 1 Network Analyzer 2 Network Analyzer Co= Cp + 0.25 pF* Cp 3 *Case Parasitics R M L M C M 0.5 pF* 0.5 pF* Power Test: 3 P INCIDENT 50 Ω Source at P REFLECTED F C 1 Low-Loss Matching Network to 50 Ω Case Design 3 2 C G B CW RF Power Dissipation = -P P INCIDENT REFLECTED H F Typical Application Circuits D (3 places) Typical Low-Power Transmitter Application: Modulation Input 200k Ω E A J (2 places) MPS-H10 45° +9VDC 47 C1 1 L1 Millimeters (Antenna) 2 Inches Dimensions Min C2 ROXXXX Bottom View 3 RF Bypass A B 470 C Typical Local Oscillator Application: Output +VDC C1 1 L1 Bottom View 3 3.50 Max 0.366 0.125 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 J C2 ROXXXX Min 3.18 2.50 H 2 Max 9.30 1.02 1.40 0.040 0.055 RF Bypass RF Monolithics, Inc. Phone: (972) 233-2903 Fax: (972) 387-9148 RFM Europe Phone: 44 1963 251383 Fax: 44 1963 251510 ©1999 by RF Monolithics, Inc. The stylized RFM logo are registered trademarks of RF Monolithics, Inc. E-mail: [email protected] http://www.rfm.com RO2125-102699 Page 2 of 2