Class D Amp with LM566, LM393 and 2XIRF530

[thimios]

I see this code typed on the ferrite 3c90
The measurement value
Scope behind the Low Pass filter
Scope after Low Pass filter.

Hi Mile,do you see a problem here?

 

[apexaudio]

Hi Mile,do you see a problem here?

No problem,
Regards

 

[thimios]

What we can use for more protection with D200?
What is your recommentation for a big class D PA amplifier?

 

[apexaudio]

What we can use for more protection with D200?
What is your recommentation for a big class D PA amplifier?

I use DC protect with triac, D2000 is PA amplifier D200 is hi-fi but can be use for small PA.

 

[thimios]

I use DC protect with triac, D2000 is PA amplifier D200 is hi-fi but can be use for small PA.

Thanks!
Is D2000 a full range amplifier or a sub amplifier?

 

[thimios]

Ok. I will share schematic and pcb after test.

Is this (D500) a tested circuit?

 

[thimios]

Is this (D500) a tested circuit?

No answer?

 

[apexaudio]

Is this (D500) a tested circuit?

No

 

[stewin]

hi apex if you bridge d200 with irfb4227 at +/-85vlts you will get 3500rms at 4ohms and 1700rms at 8ohms .
but since the protection rely on ground 0vlts to work they will not work

 

[Hadighorbani]

Try D 200 again

hi apex if you bridge d200 with irfb4227 at +/-85vlts you will get 3500rms at 4ohms and 1700rms at 8ohms .
but since the protection rely on ground 0vlts to work they will not work

hi
good day
i can find IRFB4227 and TIP31
i want create D200 again
can you offer to me a good and tested PCB for it with + - 70 volt please?
thank you

 

[thimios]

It's a ETD29 .
Changing the 510R up to 4k7 i can't see anything higher than 350 KHz.
At 350 KHz the measurement remaining oscillation after Low pass filter is 900 mV RMS.

Isn't possible to play well at 350 Khz. When volume is low everything is ok but increasing the volume amplifier crackles and stops.
Putting the 510R in position again everything seems to be ok.

 

[Pafi]

How big is air gap?

 

[thimios]

How big is air gap?

Air gap was made using a fat mica insulator,i haven't a micrometer

 

[apexaudio]

Isn't possible to play well at 350 Khz. When volume is low everything is ok but increasing the volume amplifier crackles and stops.
Putting the 510R in position again everything seems to be ok.

Resistor value of 510R must be decrease ... try with 470R or 390R...

 

[thimios]

Resistor value of 510R must be decrease ... try with 470R or 390R...

What is the result in oscillating frequency when 510R degreased? lower or higher frequency?

 

[apexaudio]

What is the result in oscillating frequency when 510R degreased? lower or higher frequency?

Higher

 

[thimios]

Higher

No,i try both values,then i connect a 1k trimer.
Putting enything lower than 510R the frecuency is lower and the amplifier is unstable(smoking zobel).

 

[ChingTan]

my d200 is working very nice in low volume,
but i also have that cracking sound i can't play in loud and i dont have oscilloscope i cant see what is happening so i just try to copy the gate resistor of other amp with irfb4227 they using 10r so i copy and replace the 47r with 10r and it sound louder than before but i can still hear the the crack in heavy bass my amp is louder than before now hoping experts can try this nice sounding amp and improve or fix some issue

 

[Pafi]

Air gap was made using a fat mica insulator,i haven't a micrometer

If you need a micrometer to measure it, then it is too thin. It should be close to 1 mm. (And of course more turns.)

Saturation current=250A*air gap (in mm) / turns. For example 20 turns with 0.2 mm gives only 2.5A

 

[thimios]

If you need a micrometer to measure it, then it is too thin. It should be close to 1 mm. (And of course more turns.)

Saturation current=250A*air gap (in mm) / turns. For example 20 turns with 0.2 mm gives only 2.5A

Pafi,i haven't a micrometer but i have an LCR Meter.Look this measurement.