Ferrite magnet as toroid transformer

[ramonegumpert]

Dear Experts

I have a 1.5 cm ring magnet, you know, the black color type of common low magnetic power magnet.

I wrapped 5 turns of copper wire around it on one side and then wrapped 10 rounds of another copper wire around it . I connected 5v battery to the 2 ends of the primary coil which is the 5 turn winding.

I then measured with volt meter the secondary coil. I did not see the output voltage at the secondary coil increase.

This is my noobie attempt. Please comment what could be wrong.

Can a ferrite magnet be used to step up voltage?

I want to step up the voltage by around 2 volts.

Many Thanks.

regards
Ramone

 

[vk6kro]

Transformers only work on AC signals, so you would have to switch your battery current on and off through the primary winding to see anything on the secondary.

However, a ferrite magnet would be a poor choice for a transformer core. Better options would be normal ferrite or soft iron laminations from a transformer.

 

[Bob S]

Are you talking about a toroidal "refrigerator" permanent magnet made of "hard" ferrite? You will need up to 300,000 amp-turns per meter. See attached table from http://www.what-are-magnets.com/10STRONTIUMCERAMIC.HTM

 

[ramonegumpert]

Dear Experts
So , what is the recommended way to stepup a 5v dc battery pack to 8volts, occupying minimal space? Kindly please offer me an idea.

I have sen videos demonstrating how a joule thief can light up a 3v led using just 1.5v. I wonder can this toroid be modified/ used as-is to function as transformer ?

Yes, i am using a toroidal fridge magnet.
its ferrite but permanently magnetised, i think. Is the effect different than a non-magnetised ferrite?

Cheers

 

[Bob S]

Dear Experts
So , what is the recommended way to stepup a 5v dc battery pack to 8volts, occupying minimal space? Kindly please offer me an idea.

Use a boost converter, which are transformerless:http://www.linear.com/products/step-up_(boost)_regulators
Other mfgrs also make similar chips.

I have sen videos demonstrating how a joule thief can light up a 3v led using just 1.5v. I wonder can this toroid be modified/ used as-is to function as transformer ?

Yes, i am using a toroidal fridge magnet.
its ferrite but permanently magnetised, i think. Is the effect different than a non-magnetised ferrite?

Magnets are not suitable for transformers.

 

[ramonegumpert]

Thanks so much Bob S. I will get a ferrite toroid and try again.

Cheers :)

 

[Bob S]

Thanks so much Bob S. I will get a ferrite toroid and try again.

If you need to make a toroid transformer circuit, be sure to use a soft ferrite. I personally would search for a boost regulator circuit from Linear.com, using a DIP package. How many milliamps do you need? I have built ferrite transformer circuits before, and the boost regulators are easier.

 

[ramonegumpert]

Dear Bob

Thanks for your reply.

I am looking at output of as high as 500 milliamps, input voltage of any between 9v to 12 v and output of 5.5 to 6v.

Is it possible to get free samples of 1 or 2 units for testing?

Thanks.

Regards
Ramone

 

[vk6kro]

You get free samples if someone thinks you might buy $500 worth of something. So, they ask who you work for and what your position is.

So, unless you are likely to buy a lot of something, you shouldn't ask for free samples.

Almost free, though, are these on Ebay:
http://www.ebay.com.au/itm/DC-DC-Converter-Buck-Step-Down-Voltage-Module-4-75-24V-0-93-18V-2-5A-Output-/270940113628?pt=AU_Gadgets&hash=item3f154a0adc

Synchronous rectification, Max efficiency up to 98%.
Input: 4.75-24V.
Output: 0.93V-18V ( Buck Mode, the input must be 2V higher than output ).
Output Current: continuous 2.5A ( Peak 4A).
Price about $3.50 US.

Which country are you in?