This Product Selection Guide contains information to help select products in the Helical Filters category on DigiKey.com
Helical Filters are designed to remove unwanted frequencies from a circuit. Items in this family use a spirally wrapped wire around a central core. Their center frequencies range from 216 MHz to 1.015 GHz with a bandwidth of 2.6 to 25 MHz, and an insertion loss of 2.5 to 6 dB.
SelectionCharacteristics
Frequency - Center: Indicates the midpoint of a filter’s pass-band; the range of frequencies that is minimally attenuated by the filter.
Bandwidth: Refers to the span of frequencies covered by the band. For example, a device with a frequency of 10MHz and a bandwidth of 2MHz, typically signifies the band of frequencies between 9MHz and 11MHz. Carefully consult the datasheets to ensure the device you choose covers the correct band of frequencies for your application.
Selectivity: Characterizes the amount by which a filter attenuates out-of-band signals, at the indicated offsets from the center frequency.
Ripple: Characterizes the amount by which a filter’s transfer function varies within its pass band.
Insertion Loss: A measure of power losses incurred by signals passing through a device, under manufacturer-defined test conditions.
Mounting Type: Indicates how the device is attached.
ProductExamples
| MFR PART # | 477MS-1035A=P3 |
|---|---|
| DIGI-KEY PART # | TKS5437TR-ND - Tape & Reel (TR) |
| MANUFACTURER | Toko America Inc. |
| DESCRIPTION | HELICAL FILTER 915MHZ CENTER |
| DATASHEET | Click Here |
| MFR PART # | 5HT-51535AS-515 |
|---|---|
| DIGI-KEY PART # | TK5405-ND |
| MANUFACTURER | Toko America Inc. |
| DESCRIPTION | HELICAL FILTER 515MHZ CENTER |
| DATASHEET | Click Here |
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