The **SFSKA5M50CF00-R3** is a high-performance **Ceramic Filter** manufactured by Murata Electronics. It belongs to the SFECV/SFSKA series, which are primarily designed for use in FM receiver intermediate frequency (IF) stages. --- ### 1. General Specifications The part is a surface-mount device (SMD) that acts as a band-pass filter, allowing a specific frequency range to pass while attenuating others. | Parameter | Specification | | :--- | :--- | | **Center Frequency (fc)** | 5.500 MHz | | **Bandwidth (3dB)** | Typically ±50 kHz to ±80 kHz | | **Insertion Loss** | 6.0 dB max (varies by sub-type) | | **Input/Output Impedance** | 600 $\Omega$ | | **Package Type** | SMD (Small footprint) | | **Mounting Type** | Surface Mount | --- ### 2. Key Features * **Miniaturization:** Designed with a low profile and small footprint to save PCB space in portable devices. * **High Selectivity:** Provides sharp attenuation characteristics to prevent interference from adjacent channels. * **Stability:** High thermal stability and mechanical vibration resistance due to the ceramic piezoelectric material. * **Lead-Free:** Compliant with RoHS standards. --- ### 3. Application Areas This specific filter frequency (5.5 MHz) is commonly used in global communication and broadcasting standards. * **Television Receivers:** Used in the Sound IF (Intermediate Frequency) stage for processing audio signals in analog/digital hybrid systems. * **FM Radios:** Used for signal filtering to ensure clear audio reception. * **Wireless Communication:** Employed in receivers that require precise narrow-band filtering at the 5.5 MHz frequency mark. --- ### 4. Typical Circuit Integration In a standard circuit, the filter is placed between the mixer and the IF amplifier. ```mermaid graph LR A[Mixer Output] --> B[Matching Resistor 600 ohm] B --> C[SFSKA5M50CF00 Filter] C --> D[Matching Resistor 600 ohm] D --> E[IF Amplifier] ``` *Note: Since the impedance is 600 $\Omega$, impedance matching resistors or transformers are often required if the surrounding ICs operate at different impedance levels (e.g., 50 $\Omega$).* ---