RF1238 Datasheet | RF Monolithics

.. ® RF1238 318.0 MHz SAW Filter - - - - - Ideal Front-End Filter for 318.0 MHz Wireless Receivers Low-Loss, Coupled-Resonator Quartz Design Simple External Impedance Matching Rugged TO39 Hermetic Package plies with Directive 2002/95/EC (Ro HS) Pb The RF1238 is a low-loss, pact, and economical surface-acoustic-wave (SAW) filter designed to provide front-end selectivity in 318.0 MHz receivers. Receiver designs using this filter include superhet with 10.7 MHz or 500 k Hz IF, direct conversion and superregen. Typical applications of these receivers are wireless remote-control and security devices operating in the USA under FCC Part 15, in Canada under Do C RSS-210, and in Australia. This coupled-resonator filter (CRF) uses selective null placement to provide suppression, typically greater than 40 d B, of the LO and image spurious responses of superhet receivers with 10.7 MHz IF. RFM’s 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 excellent frequency stability over a wide temperature range. TO39-3 Case Electrical Characteristics Characteristic Nominal Frequency at 25°C Insertion Loss 3 d B Bandwidth Rejection at f C - 21.4 MHz (Image) at f C - 10.7 MHz (LO) Ultimate Temp. Characteristics Operating Case Temp. Turnover Temperature Turnover Frequency Freq. Temp. Coefficient Frequency Aging External Impedance Match Series Inductance Shunt Capacitance (Tab Side, Non Tab Side) Lid Symbolization (in addition to Lot and/or Date Codes) TC TO f O FTC If AI L C 5 1 3, 4 -40 30 45 f C+4 0.032 ≤10 86 6.8 on Pin 1 Side, 4.7 on Pin 2 Side RFM RF1238 1 Absolute Frequency Tolerance from 318.0 MHz Sym f C ∆f C IL BW3 Notes 1, 2 1 1, 2 500 40 15 Minimum Typical 318.0 ±80 1.7 700 50 40 80 +85 60 °C °C k Hz ppm/°C2 ppm/yr n H p F d B 3.5 800 Maximum Units MHz k Hz d B k Hz CAUTION: Electrostatic Sensitive Device. Observe precautions for handling. Notes: 1....