Would it be safe to replace a ferrite bead that had a rating of 47 ohm @ 100MHz 5A with one that is 70 Ohms @ 100MHz 6A?

I can't seem to find an exact replacement.

https://www.amigawiki.org/dnl/schematics/A4000_Rb.pdf - fb177 for example.

  • 3
    \$\begingroup\$ Depends on the application, post a schematic. Post both model numbers, or even better, the frequency graphs for both. \$\endgroup\$
    – Voltage Spike
    Oct 7, 2019 at 17:00
  • 1
    \$\begingroup\$ Without giving us the application, it's like asking if it's okay to replace a car with a truck. \$\endgroup\$
    – Bort
    Oct 7, 2019 at 17:39
  • \$\begingroup\$ I posted the schematic. I don't have a model number of graph for the original. \$\endgroup\$
    – Oggie
    Oct 7, 2019 at 17:50
  • \$\begingroup\$ Those singular numbers you give are pretty much useless for evaluating ferrite beads. You need frequency vs impedance curves. \$\endgroup\$
    – DKNguyen
    Oct 7, 2019 at 18:14
  • \$\begingroup\$ what are your troublesome frequencies? \$\endgroup\$ Oct 8, 2019 at 2:13

2 Answers 2


Sure you can, IMO the second is even better choice since it has a higher impedance at rated frequency, which means it will attenuate more radio interference that it will catch in external IO wires acting like antenna. At the same time it can pass more DC current 6A vs 5A, it will have lower impedance at DC.


Looks like a good choice to absorb some emissions for +5V user external use as long as you use twisted pair wires and a low ESR user load cap to regulate the load transients.


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