A comparison of broadband ferrites from 4 manufacturers
Posted by: Huge on 07 February 2016
Manufacturers
Meisongbei (often supplied as 'generic' components)
Fair-Rite
TDK
Würth Elektronik
All are doped NiZn ferrites
Data Sheets
http://www.rapidonline.com/ele...e-cable-cores-518991 (Meisongbei)
http://www.rapidonline.com/pdf/1808831.pdf (Fair-Rite)
https://product.tdk.com/info/e..._cylindricale_en.pdf
http://www.farnell.com/datasheets/1789626.pdf (Würth)
Observations on the Spec Sheets:
Meisongbei UF (SF) series (sometimes known as 30 material)
These use a clone of Fair Rite's 43 or 44 material. They are broadly similar in performance. Complex impedance decreases progressively with decreasing frequency. Rated 1MHz to 300MHz. These have usable impedance to about 400MHz or 500MHz with limitations.
Fair-Rite
43 or 44 material. Similar to Meisongbei UF (SF) series, but some have a bit higher complex impedance across the board. Rated 1MHz to 300MHz. These some usable impedance to about 400MHz or 500MHz with limitations.
TDK RU series
HF70 material. These have a much flatter complex impedance / frequency curve. Rated 1MHz to 400MHz. These may have usable impedance to about 500MHz or 600MHz with limitations. Low frequency complex impedance (1Mhz and below) isn't specified but is likely to be better than Meisongbei or Fair-Rite 43 or 44 materials.
Würth Elektronik Star-Tec series
Material 4 W 620. This components seem to show a complex impedance decreasing progressively with decreasing frequency, but this seems to be about twice as high as the Meisongbei SF or Fair-Rite 43 or 44 components. In addition at HF, reasonable impedance is maintained to 1GHz. At LF (1Mhz and below), the higher overall impedance allows these to compete with the TDK components.
Conclusions:
TDK HF70 has a broader / flatter frequency response than Meisongbei or Fair-Rite 43 or 44 materials, but a lower overall impedance potential.
Würth Elektronik Star-Tec components seem to offer the best broadband performance of those types I compared, but this performance comes with a price premium.