I am finding it difficult to get an inductor core for my 4K5 amplifier I am building but l heard you can make your own inductor core from flyback ferrite core.can someone help me.
It would be easiest to just select a pre-wound standard inductor, since there are many available for amplifiers and power supplies. Mouser has many ready to use Inductors available. If you want a class D amplifier with low distortion, then the magnetic core should have a small hysteresis loop & the inductor should handle all the current with no saturation.
Wurth has some nice standard inductors for Class D amplifiers....
Single Coil Inductors
WE-LHMD SMT High Current Inductor, Digital Audio
WE-HIDA THT High Current Inductor Digital Audio
CoilCraft also has Inductors specifically for Class D amplifiers
If you wish to wind your own, then you need to choose the proper low loss material and choose a form factor for the core. There are a lot of options.
Here is one supplier of core material, which I used years ago: Ferroxcube: Data handbook
Overview Cores & Accessories: https://www.ferroxcube.com/en-global/products_ferroxcube/index/Overview
Here is the power conversion page: https://www.ferroxcube.com/en-global/download/download/11
Materials Brochure page: https://www.ferroxcube.com/en-global/download/index/material_brochure
Design Tool: https://www.ferroxcube.com/en-global/design_tool/index
On the longshot that you'd have access to PC motherboard or graphic card discards, there's often such inductors on these which could be harvested.
I think the above answer is a little bit better. Just sayin'
I think the above answer is a little bit better. Just sayin'
If those surplus inductor cores are well marked, one can look up the manufacturer specifications. With unknown core material, it is is just a WAG, unless one does the measurements to characterize the material.
There are a lot of suitable ferrite materials like Epcos N87 on the market, Wuerth & Coilcraft being the most expensive. Brands like ferrocore deliver similar stuff at half the price.
If you are in for lowest distortion you have to minimize the excursion of flux intensity at max current significantly below saturation level (300~400mT). This can be achieved using the biggest core-areas and big gaps as well - requiring additional turns of windings increasing copper losses. There is no free lunch...
If you are in for lowest distortion you have to minimize the excursion of flux intensity at max current significantly below saturation level (300~400mT). This can be achieved using the biggest core-areas and big gaps as well - requiring additional turns of windings increasing copper losses. There is no free lunch...