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Wound Beads (2944666681)

Part Number: 2944666681
44 Material
Suppression Components
Board Component
Printer Friendly Data Sheet
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Part Number: 2944666681


Explanation of Part Numbers:
– Digits 1 & 2 = Product Class
– Digits 3 & 4 = Material Grade
– Last digit 1 = Bulk Packed 4 = Taped and Reeled

Six and eleven hole beads, in two NiZn materials, are available both as beads (product class 26) and wound with tinned copper wire in several winding configurations (product class 29).

Wire used for winding is oxygen free high conductivity copper with 100% matte tin plating over a nickel undercoating.

Recommended storage temperature and operating temperature is -55 °C to 125 °C

Recommended Soldering Profile

Packaging Options:
– Parts with a 1 as the last digit of the part number are supplied bulk packed. Wound beads with part numbers 29–666631 and 29–666651 can be supplied radially taped and reeled per IEC 60286-1 and EIA 468-B standards. For these taped and reeled wound beads the last digit of the part number is a 4. Taped and reeled wound beads are supplied 500 pieces on a 13 reel.

For any wound bead requirement not listed in here, please contact our customer service group for availability and pricing. 

Catalog Drawing
3D Model

Weight: 1.4 (g)

Dimmmmm tolnominal inchinch misc.
Winding Information
Turns TestsWire Size1st Wire Length2nd Wire Length
2 x 1½0.53
24 AWG
38.0 ±3.0
28.0 ±3.0

Chart Legend
+ Test frequency
•A ½ turn is defined as a single pass through a hole.

Typical Impedance (Ω)
1 MHz52
10 MHz+245
50 MHz+495
100 MHz+570
200 MHz565

Beads are controlled for impedance limits only. Minimum impedance values are specified for the + marked frequencies. The minimum impedance is typically the listed impedance less 20%.

Catalog Drawing

The 44 material beads and wound beads are tested on the E4990A Impedance Meter. The 61 material parts on the E4991A / HP4291B Impedance Analyzer.

Typical Impendance (Ω)
1 MHz 45
10 MHz+ 213
50 MHz+ 400
100 MHz+ 470
200 MHz 380

CSV Download

A NiZn ferrite developed to combine a high suppression performance, from 30 MHz to 500 MHz, with a very high DC resistivity.

Available in 44 material:
SM Beads
PC Beads
Wound Beads
Round Cable Snap-Its
Connector EMI Suppression Plates

44 Material Characteristics
Property Unit Symbol Value
Initial Permeability@ B < 10 gauss µi 500
Flux Density @ Field Strength Gauss
Residual Flux Density Gauss Br 1100
Coercive Force Oersted Hc 0.45
Loss Factor @ Frequency 10 -6
Tan δ/ µi 150
Temperature Coefficient of Initial Permeability (20 -70°C) % / °C 1.6
Curie Temperature °C Tc >160
Resistivity ohm-cm ρ 1×109

**** Characteristic curves are measured on standard Toroids (18/10/6 mm)  at 25°C and 10 kHz unless otherwise indicated. Impedance characteristics are measured on standard shield beads (3.5/1.3/6.0 mm) unless otherwise indicated.

Material Safety Data Sheet (MSDS)

Click here to download Complex Permeability vs. Frequency (CSV)

Ferrite Material Constants

Specific Heat
0.25 cal/g/°C
Thermal Conductivity
3.5 - 4.5 mW/cm-°C
Coefficient of Linear Expansion
8 - 10x10-6/°C
Tensile Strength
4.9 kgf/mm2
Compressive Strength
42 kgf/mm2
Young's Modulus
15x103 kgf/mm2
Hardness (Knoop)
Specific Gravity
≈4.7 g/cm3
The above quoted properties are typical for Fair-Rite MnZn and NiZn ferrites.

Storage and Operating Temperature
Printer Friendly Data Sheet - Download as pdf file

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