Passive Filters

Passive filters are a subtype of passive components that play key roles in the design and function of many electronic circuits. Passive filters help block unwanted frequencies, ensuring the delivery of appropriate frequency characteristics to the main circuit.

We work with respected manufacturers like TDK, Schaffner, TE Connectivity and EPCOS, and stock a range of passive filters under our RS PRO brand for even better value.

Types of passive filters and their common uses

  • Band Pass Filters act as signal gatekeepers, allowing specific frequencies (the ‘passband’) through while blocking signals outside a stated range.

    • They’re often used to clean up signal interference in radio transmission and communications circuits

  • Power Line Filters help prevent degradation in circuit performance when an electronic device is connected to an external power line, minimising conducted frequencies like radio (RFI) or electromagnetic (EMI) interference.

    • They’re found in single phase, three phase or DC (direct current) power applications across a huge range of devices and systems, helping reduce undesired circuit behaviour

  • SAW Filters use transducers to convert electrical input signals to an acoustic wave and back again, and are widely used in mobile phone/tablet touchscreen technologies.

    • Broad operating temperature ranges also make them useful in heavy industrial environments like chemical, optical or thermal processing plants

  • Signal Filters clean up electrical signals through noise reduction processes, often built around multilayer ceramic capacitors, inductors, dielectric resonators and crystals.

    • They’re important components in audio, video, communications and broadband circuitry, and have a number of frequency filter response types including high-pass, low-pass, band-stop, and cut-off

  • Sinusoidal Filters are low-pass components intended to block or impede high-frequency PWM signals, converting them to a smooth wave voltage.

    • Useful for protection against premature circuit damage and component stress, voltage spikes, cable stripping, current loss and overheating

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