Ferrites for EMI suppression
- Technology
- Ferrite cores
- Partner
- Ferroxcube
EMI suppression is a critical point in electronic/electric products that engineers need to consider in the early stages of product development. High permeability ferrites offer the best solution in terms of efficiency and cost.
Working temperature, flux density, high impedance, and initial permeability are key parameters to select the proper material.
Ferrites in this range are made of both alloys, manganese zinc (MnZn) and nickel-zinc (NiZn) at a slightly higher cost solution.
Shapes that typically are used in this application are toroids and U for CMC, cable shields, beads, rods, and balun.
Material names in this range start with 3Ex. Examples are 3E10 and 3E65 covering a range of permeability 5K to 15K; or with 3Sx like 3S4, optimised for frequencies from 10MHz up to 300MHz; or 4Sx like 4S3, made of NiZn for range 30MHz to 1GHz.
Range features
A high level overview of what this range offers
- Medium cost materials (NiZn & MnZn)
- Development trend:- Increase frequency range for high impedance- Increase permeability stability through temperature- Increase Bsat VS Temp
- Available shapes: toroids, E, U, BD, BDS, BDW, MLS, CMS, RODs, cable shields, WBS, and WBC
- Permeabilities above 4000 for 3Ex
- Low permeabilities for 3Sx and 4Sx
- Low Curie temperature: between 110°C and 255°C
- 3Ex series also used for wideband signals, pulse transformers, and delay lines
What’s in this range?
All the variants in the range and a comparison of what they offer
High permeability materials
| Material | µi at 25°C | Bsat (mT) at 25°C | Tc (°C) | Ferrite type | Notes |
|---|---|---|---|---|---|
3C11 | 4300 | 390 |
| MnZn | Frequency < 30MHz |
3E65 | 5200 | 480 |
| MnZn | Frequency < 20MHz |
3E25 | 6000 | 390 |
| MnZn | Frequency < 20MHz |
3E27 | 6000 | 430 | ≥ 150 | MnZn | Frequency < 20MHz |
3E26 | 7000 | 430 | ≥ 155 | MnZn | Frequency < 20MHz |
3E10 | 10000 | 460 | ≥ 130 | MnZn | Frequency < 20MHz |
3E6 | 10000 | 460 | ≥ 130 | MnZn | Frequency < 15MHz |
3E12 | 12000 | 470 | ≥ 130 | MnZn | Frequency < 15MHz |
3E15 | 15000 | 470 | ≥ 130 | MnZn | Frequency < 15MHz |
Low permeability materials
| Material | µi at 25°C | Bsat (mT) at 25°C | Tc (°C) | Ferrite type | Notes |
|---|---|---|---|---|---|
3B1 | 900 | 380 | ≥ 150 | MnZn | |
3S1 | 4000 | 400 | ≥ 125 | MnZn | Frequency < 30MHz |
3S3 | 350 | 320 | ≥ 225 | MnZn | Frequency < 200MHz |
3S4 | 1700 | 320 | ≥ 110 | MnZn | Frequency < 100MHz |
3S5 | 3800 | 545 | ≥ 255 | MnZn | Frequency < 30MHz |
4B1 | 250 | 360 | ≥ 250 | NiZn | Frequency < 300MHz |
4S2 | 850 | 340 | ≥ 150 | NiZn | Frequency < 100MHz |
4S2F | 700 | 290 | ≥ 120 | NiZn | Frequency < 100MHz |
4S3 | 250 | 360 | ≥ 250 | NiZn | Frequency < 300MHz |
4S60 | 2000 | 260 | ≥ 100 | NiZn | Frequency < 50MHz |
