I'm doing a D-Series Digital Amplifier. But in my work there is a pwm going between 62khz-500khz for my frequency comperator. According to this, I tried very different different nüve, but some did not work, some of them worked shortly after the mosquitler burned, and some of the coil began to be like flame.
When I look at the color codes of these cores, the frequency value '' AL '' VALUE writes tut For example, I have to keep the value of 150uh, but I wonder if the escape had caught this value in different values, it could always be a problem?
The last time I used the Toroid Core T157-15 RED - WHITE.
The Buddha started to heat the coil
When I look at the color codes of these cores, the frequency value '' AL '' VALUE writes tut For example, I have to keep the value of 150uh, but I wonder if the escape had caught this value in different values, it could always be a problem?
The last time I used the Toroid Core T157-15 RED - WHITE.
The Buddha started to heat the coil
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Micrometals Powder Core Solutions
At least according to the Micrometals colour codes, red-white is material -15.
https://micrometalsarnoldpowdercores.com/pdf/mix/Mix-15-DataSheet.pdf
While it has over double the permeability of the more often used material -2 (red-clear), at least going by the specs in the small table on the top-right, looks like it also has almost double the core losses .
https://micrometalsarnoldpowdercores.com/pdf/mix/Mix-2-DataSheet.pdf
150uH is a HUGE value for an output filter inductor, though......
At least according to the Micrometals colour codes, red-white is material -15.
https://micrometalsarnoldpowdercores.com/pdf/mix/Mix-15-DataSheet.pdf
While it has over double the permeability of the more often used material -2 (red-clear), at least going by the specs in the small table on the top-right, looks like it also has almost double the core losses .
https://micrometalsarnoldpowdercores.com/pdf/mix/Mix-2-DataSheet.pdf
150uH is a HUGE value for an output filter inductor, though......
On my class d amp it is 10uH and 470nf filter.
I used a T106-2 core with about 10 turns on it.
You will need to use quite thick wire to take the power.
I used a T106-2 core with about 10 turns on it.
You will need to use quite thick wire to take the power.
The current rating of the inductor is very important. If you wind your own you have to know how to calculate the rating for yourself from the ferrite material data and core-size. Overloaded inductors can overheat the wire itself or the ferrite or both.
Gapped inductors are worth considering, much more stable, although larger.
150µH is about 60 ohms of impedance at 62kHz, its clearly completely the wrong value for any of that PWM range.
Gapped inductors are worth considering, much more stable, although larger.
You must stick to a single PWM freuquency, the output filter is tailored specifically to a single frequency.
150µH is about 60 ohms of impedance at 62kHz, its clearly completely the wrong value for any of that PWM range.
where the coil 150 is working with almost no heat with a gray core. No problem. However, the red white Amidon t157-15 cores and 140 uh worth the flame is like.
22uh coil and red-gray mosquitos are burning right.
22uh coil and red-gray mosquitos are burning right.
Huge old FETs + (relatively) large gate resistors = SLOW switching times
Dead time is whatever the propagation delays and transition times the CD4070 has (supplied at 12V, that easily adds up to some hundreds of ns).
Well, if a "gray core" inductor works without burning up, use that.
Why do you need / want to use the -15 material core?
And once again, why do you need a 150uH output inductor?
Dead time is whatever the propagation delays and transition times the CD4070 has (supplied at 12V, that easily adds up to some hundreds of ns).
Well, if a "gray core" inductor works without burning up, use that.
Why do you need / want to use the -15 material core?
And once again, why do you need a 150uH output inductor?
Do the MOSFETs get hot / burn out without any inductor connected?
And more importantly, do you have an oscilloscope?
And more importantly, do you have an oscilloscope?
Unless my math is totally messed up, that works out to a whopping 466uH 😱
360nH * (36 * 36) = 0.36uH * 1296 = 466.56uH
Then again, checking the datasheet, that "360" is actually expressed in uH/100 turns, which changes things a bit - that works out to 36nH/turns^2.
36 * 36 * 36 = "only" 46.6uH
So, interestingly enough, the value is more "terrestrial", but the material may well still be unsuitable for this application (especially at those supply voltages), given its nearly double core losses compared to the -2 material.
360nH * (36 * 36) = 0.36uH * 1296 = 466.56uH
Then again, checking the datasheet, that "360" is actually expressed in uH/100 turns, which changes things a bit - that works out to 36nH/turns^2.
36 * 36 * 36 = "only" 46.6uH
So, interestingly enough, the value is more "terrestrial", but the material may well still be unsuitable for this application (especially at those supply voltages), given its nearly double core losses compared to the -2 material.
They gave AL in stupid units? Normally its nH/turn^2 and the table I found didn't state the units (definite no-no that). Further investigation reveals the Amidon tables say "µh" instead of "µH" for microhenries, which is so slovenly its pretty much innumeracy in my book. Don't get me started on "0.001µF" and "10,000pF"
Yabbut. You live in the UK and we have adopted sensible SI units. Blame the French.
Obviously once we get out of the EU we can adopt the American system along with chlorinated chicken, hormone fed beef and GM modified food.
All you have to do is remember to multiply/divide by 10,000 or that other number and factor in/out the appropriate number of pi's as and when needed or not and you're good to go.
It's why Americans have smaller pints and weaker beer. They need to be sober in order to get the sums right. You can polish off six pints of Timmy Taylor's porter Friday afternoon and still get things less than a factor of Two or Three Pi Thousand out.
Obviously once we get out of the EU we can adopt the American system along with chlorinated chicken, hormone fed beef and GM modified food.
All you have to do is remember to multiply/divide by 10,000 or that other number and factor in/out the appropriate number of pi's as and when needed or not and you're good to go.
It's why Americans have smaller pints and weaker beer. They need to be sober in order to get the sums right. You can polish off six pints of Timmy Taylor's porter Friday afternoon and still get things less than a factor of Two or Three Pi Thousand out.
Well, first i googled for their part, and found the product page. You'll note the AL doesn't actually have any units specified there. And since "assumption is the mother of all f**k-ups"... 🙄
T157-15 - Amidon
Then i went into their "Specifications" section and dug up the datasheet for material -15, and there it is...
http://www.amidoncorp.com/product_images/specifications/1-07.pdf
T157-15 - Amidon
Then i went into their "Specifications" section and dug up the datasheet for material -15, and there it is...
http://www.amidoncorp.com/product_images/specifications/1-07.pdf
sounds like your core material is too slow or lossy creating heat and voltage spikes on transition. the T 106 material works well.
I can run my amp with 42v rails up to 1.5mhz with a 15uh 6 amp inductor with very little heating.
I can run my amp with 42v rails up to 1.5mhz with a 15uh 6 amp inductor with very little heating.
T106 is a core size, not a material.
That, and the OP, at least according to the schematic attached to post #5, is trying to use this with +/-85V rails.
That, and the OP, at least according to the schematic attached to post #5, is trying to use this with +/-85V rails.
Gray-white ferrite and RM14 150Uh -220 UH coil winding is overheating.
Red - I'm using the black core is heating up the wire is burning.
Speaker icons to the output sound normal.
At the exit 10ohm, 470nf warms up.
How can I solve this problem?
Why does the coil overheat? What should I do?
Red - I'm using the black core is heating up the wire is burning.
Speaker icons to the output sound normal.
At the exit 10ohm, 470nf warms up.
How can I solve this problem?
Why does the coil overheat? What should I do?
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