Ceramic Filters

Introduction of Filters
For more than two decades, piezo technology has been instrumental in the proliferation of solid state electronics. A view of the future reveals that even greater expectations will be placed on piezoelectric material in the area of new applications and for more stringent performance criteria in modern products.

Token sophisticated ceramics technology has greatly increased selectivity and wide-band characteristics, and has stabilized the characteristics of ceramic filters. The series covers a wide range of attenuation and bandwidths to allow selection of the most optimum filter characteristics for each application.

Token filters are bandpass filters consisting of one or more ceramic resonators connected in a ladder network configuration. Passband characteristics are determined by the relative resonant and anti-resonant frequencies of the resonators. Both narrow and wide passband configurations are manufactured by adjusting the resonator frequency characteristics.

The IC (Integrated Circuit) has found wide use in the field of commercial equipment, such as automotive radios, stereo systems, 2-way communications, TV sets, etc. Thus, new miniature integrated filters, with high performance, are extremely desirable for use in IF circuits.

Furthermore, radio wave disturbance due to rapid progress of data transmitting rate and remarkable sophistication of communication network have become significant traffic conflicts. Accordingly, the demand for filters with high selectivity and wide pass band width has boosted.

The IC application of the active elements will continue its progress, and there will be a growing demand for highly selective, non-adjustable, miniature and wide pass band width IF circuit.

Advantage of Token Piezoelectric Filters
Token Electronics had been able to develop specialized piezo materials which when combined with an advance design have resulted in a complete line of practical, inexpensive piezo devices for entertainment and communications applications.

Token reliably deliver high-quality components according to the each customer special needs with respect to performance, costs, and technology modifications.

For marketing discontinuations or sourcing activities concerning Piezoelectric Filter products, you are encouraged to contact our Sales Department so the request can be properly directed within Token.

Download complete Product Catalogue And Datasheet PDF file (912KB).

for FM Series

ThumbnailDescription Type Frequency Range Murata Filter (P/N)

  • 1 (LTCS10.7M) Surface Mount Chip 10.7 MHz SFECS10M7 Token LTCS10.7M chip filter for FM-receiver utilizes the latest piezoelectric ceramic technology enabling the most cost-effective designs. The LTCS10.7M constructs with piezoelectric element which is connected in the sandwich shape by ceramics substrate. With a small mounting area (3.45±0.2 x 3.1±0.2 mm) and super thin profile (1.4 mm max.) enables flexible PCB design. Products conform to the RoHS directive.
    LTCS10.7M Series - PDF (318KB)

  • 2 (LTCA/CV10.7M) Surface Mount Chip 10.7 MHz SFECV10M7 SMD LTCA/CV10.7M for AM (Compatible to Murata filter SFECV10M7) has been made smaller, thinner and in a chip configuration for surface mounting. The dimensions of LTCA/CV10.7M chip filter is small as 7.0±0.3 x 3.0±0.3 mm with low profile 1.5±0.2 mm. Insertion Loss max(dB) is from 3.0 db ~ 10 db, Spurious Attenuation (9~12 MHz) min(dB) 30 db ~ 35 db with Input/Output Impedance: 330Ω. Various bandwidths are available. Select a suitable type in accordance with the desired selectivity.
    LTCA/CV10.7M Series - PDF (326KB)

  • 3 (LT10.7M) for FM Receiver Dip 10.7 MHz SFE10M7 FM-IF Token LT10.7M series are monolithic devices which utilize the energy-trapped thickness vibration-mode. This principle of operation is based upon the fact that an excellent resonating element with low spurious vibration can be obtained by adhering to certain theoretical parameters of design. These parameters include the physical dimensions of the peizo element, the electrode pattern, and the associated mass loading effect of the electrodes. (Compatible to Murata SFE10M7 FM-IF)
    LT10.7M Series - PDF (354KB)

  • 4 (LT10.7M A10) Low Insertion Loss Dip 10.7 MHz SFE10M7 A10 The LT10.7M offers three series: LT10.7M for FM Receiver (Compatible Murata SFELF10M7), LT10.7M A10 Insertion Loss 2.5±2.0 db ~ 4.5±2.0 db (Compatible Murata SFELF10M7 A10), and LT10.7M Wide Band-width 950 kHz at 20dB/Narrow Band-width 95 kHz at 20dB (Compatible Murata SFELF10M7 DBS Receiver).
    LT10.7M A10 Series - PDF (354KB)

  • 5 (LT10.7M) Wide/Narrow Band-Width Dip 10.7 MHz SFE10M7 DBS LT10.7M Narrow Band-width series features stable low spurious and temperature characteristics. This series is suitable for European car-audio or AM up conversion use that needs narrow band characteristics are stable. LT10.7M Wide Band-width series are specified to make up conventional filters which wider band characteristics not obtained.
    LT10.7M Series - PDF (354KB)

for TV/VCR Stage

ThumbnailDescription Type Frequency Range Murata Filter (P/N)

  • 1 (LT MB) for 2 Channel Multi-Sound TV Dip 4.5~6.5 MHz SFE MB Token ceramic (LT MB) filters are a high selectivity filter for 2 channel multi-sound TV. Features with frequency adjustment-free, high performance and durability, and high selectivity. (Compatible to Murata Filter SFE MB series)
    LT MB Series - PDF (318KB)

  • 2 (LTT MA) High-Selectivity Dip 4.5~6.74 MHz SFT Token high-selectivity filters for TV/VCR stage (LTT MA) series is 4 element devices that offer more selectivity than the conventional LT series (Murata SFE). The improved spurious suppression of these filters eliminates the need for cascading multiple filtering devices; therefore, it is possible to design a more compact circuit board configuration.
    LTT MA Series - PDF (301KB)

  • 3 (LTS MCB/MDB) Low Spurious Dip 4.5~6.5 MHz SFSH MCB/MDB Token ceramic low spurious for TV/VCR stage (LTS MCB/MDB) filters use thickness shear vibration mode and is compatible Murata SFSH MCB/MDB. Features with excellent spurious characteristics within Video Signal Band, and 3 types bandwidths prepared to respond customer requests. LTS MCB/MDB is suitable for Multiplex Sound TV in America.
    LTS MCB/MDB Series - PDF (300KB)

for Communication

ThumbnailDescription Type Frequency Range Murata Filter (P/N)

  • 1 (LTC455/450) Surface Mountable Chip 455/450 KHz CFUCG Token ceramic (LTC455/450) chip filters for communication (Compatible to Murata CFUCG series) comprises small, high performance, thin (4.0mm) consisting of 4 ceramic elements. Their innovative construction is perfect for shrinking mobile communication products such as pocket pagers and cellular phones. The surface mount LTC455/450 U/W series for AM use is one of the most recommendable intermediate filters, having such distinctive features as high selectivity, high stability and adjustment-free operation. Additionally its easy matching with IC helps create an easy circuit design.
    LTC 455/450 Series - PDF (324KB)

  • 2 (LTM455/450) Miniature Versions Dip 455/450 KHz CFUM/WM Ceramic (LTM455/450) Filters for Communication (Compatible to Murata Filter CFUM/WM 455/450 Series) are miniaturized versions of the Murata CFU/CFWS lines. These compact, highly selective characteristics are recommended for use in applications ranging from two-way radio to auxiliary filters in high class transceivers.
    LTM 455/450 Series - PDF (291KB)

  • 3 (LT455/450 U/W) G.D.T. Characteristics Dip 455/450 KHz CF, SF Token ceramic (LT455/450 U/W) filters for communication are 4-element and 6-element devices connected in ladder form. These highly selective filters are designed to address the G.D.T. characteristics required in digital communications. The excellent G.D.T. characteristics allow these filters to be utilized in areas such as the mobile cellular markets as well as a variety of stereo applications. (Also available in 450kHz version.)
    LT 455/450 U/W Series - PDF (323KB)

  • 4 (LTP) for Standard AM Filtering Dip 450~470 KHz SFU450/455KHz Ceramic (LTP) filter for AM (Compatible to Murata Filter SFU450/455kHz ) are designed to address the needs of standard AM filtering requirements. These filters are recommended for use in low cost products where economically, efficient designs are critical.
    LTP Series - PDF (319KB)

  • 5 (LTZ) for AM Dip 450~470 KHz SFZ Ceramic (LTZ) Filter AM (Compatible to Murata Filter SFZ Series) are designed to address the needs of standard AM filtering requirements. With dimensions (7.0 x 9.0 x 6.5mm), and Insertion Loss 7db, the (LTZ) series is composition of 2 elements direct coupling. Center Frequency (fo) is available in a range of 450kHz ~ 470kHz. The nominal frequency tolerance is ±2kHz.
    LTZ Series - PDF (280KB)

  • 6 (MLT) Miniature for AM Dip 450~470 KHz PFB Ceramic (MLT) Miniature Filter for AM (Compatible to Murata Filter PFB Series) is one of the most recommendable intermediate filter, having such distinctive features as high selectivity, high stability and adjustment-free operation. Additionally its easy matching with IC helps create an easy circuit design such as applications in Electric synthesized tuners, HiFi audio systems, AM stereo demodulations, One-chip non-adjustment IC's, and even smaller, thinner set structure to cope with these diversifying for AM receiver.
    LT Miniature Series - PDF (283KB)

  • 7 (LTB) Shrinking Mobile Communication Dip 450~470 KHz - Ceramic (LTB) Filter for Communication comprises small, high performance. Their innovative construction is perfect for shrinking mobile communication products such as pocket pagers and cellular phones.
    LTB Series - PDF (339KB)

  • 8 (LTA) for Radio Cassette Recorder Dip 450~470 KHz - Ceramic (LT465A) Filter for Radio-Cassette Recorder are designed to address the needs of standard radio cassette recorder requirements. Recommend for use in low cost products where economically, efficient designs are critical. The nominal frequency tolerance is ±2KHz.
    LT465A Series - PDF (338KB)

  • 9 (LZU) Search-Stop Signal Detection Dip 450 KHz BFU Ceramic (LZU) Filter 450 kHz Search-Stop Signal Detection (Compatible to Murata Filter BFU Series) are specifically designed for signal detection circuitry used in applications such as that found in the search-stop functions of electronically tuned radios. The LZU series are narrow bandwidth filters. This filter is used in the application which detects the carrier peak with a narrow bandwidth amplifier, or an electronic tuner as a stop signal detector.
    LZU Series - PDF (274KB)

Characteristics And Properties of Filter Terminologies

What is "Ceramic Filter"?
A filter which uses a piezoelectric ceramics as an electrical-mechanical transducer and as a mechanical resonator. It provides simultaneously the electrical and the mechanical system within a single element.

Filter Characteristic Properties

An example of ceramic filter Frequency characteristicAn example of filter Frequency characteristic

Center Frequency (Symbol: f0; Unit: Hz)

It signifies the frequency in the center of the pass band width. However, the center frequency for some product is expressed at the point where the loss is minimum.

Pass Band Width (Symbol: PBW; Unit: Hz)

Signifies a difference between the two frequencies where the attenuation becomes 3dB from the level of the minimum loss point.

Insertion Loss (Symbol: IL; Unit: dB)

Expressed in the input and output level ratio at the point of minimum loss in dB. The insertion loss for some product is expressed in the input and output level ratio at the center frequency.

Ripple (Unit: dB)

If there are peaks and valleys in a pass band width, the ripple expressed the level difference of voltage between the maximum peak and minimum valley and it is expressed in dB.

Attenuation Band Width (Symbol: ABW; Unit: Hz)

Signifies a difference between the two frequencies where the attenuation becomes the specified values (dB) from the level of minimum loss.
(Example: Expressed at a point where the attenuation becomes 20 dB in case of 10.7 MHz filter.)

Selectivity (Unit: dB)

Expressed as the attenuation of the detuning point from the center frequency.
(Example: The attenuation that ±9 kHz was detuned from the center frequency in case of 455 kHz filter.)

Spurious Response (Symbol: sp; Unit: dB)

Expressed as the difference of voltage ratio between minimum attenuation point in the stop band range and minimum loss point in the pass band width by using dB (The stopped range is specified with each filter).

Spurious

Signifies the frequency response based on the parasitic (unwanted) vibration against the frequency except the fundamental vibration.

Bottom Level (Unit: dB)

Signifies the minimum or average attenuation without both main response and spurious within the specified frequency range.

Input/Output Impedance (Unit: Ω)

Signifies the internal impedance value of the input and output side at the center frequency of ceramic piezoelectricity, and it is expressed in Ω. It causes no problem even if the input and the output are used in reverse with ceramic piezoelectricity, since the input and the output impedance are in a symmetry of substantially almost same value.

Impedance Matching

When connecting one electric circuit to another, or a component to another, or one electric circuit to a component, the electric energy is supplied most efficiently from the signal source to the load if the signal source impedance and the load impedance are same.
If these impedances are mismatched, electric energy escapes in form of a reflection. To match the signal source impedance and the load impedance is called the impedance matching. This is very important for ceramic piezoelectricity, as an improper impedance matching may cause various troubles.