My class d IRS2092 project

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I don't understand, first it didn't work with 4227's, and now it does? And you just added 47uf?

Yes. I can only guess there was something wrong with my 12 volt supply.
Adding 47uf instead of the 10uf was enough to get rid of the 12 volt glitches.

What was happening was the the first HO pulse reset the 2092.
This happened because the vb took power from the 12 volts through the diode and 22uf and this caused the 12 volts to drop out a volt or so and so resetting the 2092.

Might just have been my 12 volt supply was poor and wasnt decoupled enough.
 
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ok, so then tell me what resistors and caps you have to set 2092, so I can check what is diffrent from my

Also, what is your supply voltage? and you drive 4227 directly? What Rgate do you use?

I have used the circuit in irs2092 datasheet.

Only difference is I have used maximum deadtime and changed the vcc 10uf to 47uf.

Rgate are 10R.

I use +/- 35 volts supply.
 
same freq setting elements?
you are talking about elements as for IRAUDAMP5 reference design?
can you use higher voltage? I always had +/-60

Download the datasheet for the irs2092.

Not the application note or iraudamp5.

I use same freq elements.

I havent tried a higher voltage yet.

Due to the TO220 package I am having trouble getting more than 5 amps out of the pcb tracks, so currently I cant get more than 100 watts without using 2 oz copper. WIth 2 oz copper i can get 400 watts.
 
Ok now I got is working at about 324k
elements from 1138 are way of for me and my setup
What was wrong is too low voltage for fet drives, but when I lower the resistance
(from gnd goes via R to zener for 12v supply(lower side)), I got clean sound

Thanks nigel for pushing me to test it again, i'm very happy now
What I might do is use floating supply for lower side, no more resistors like now
 
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(from gnd goes via R to zener for 12v supply(lower side)), I got clean sound


Nice to hear about it.
Its best to use separate winding from trafo of 0-15V and get a regulated 12-15V for the driver supply. Peaks upto 4A are normal in occurrence through boot diode when the output is clipping and high side boot cap needs sufficient current pulse to get charged rapidly. A low esr bulk cap is must for driver supply close to boot diode.
 
Nice to hear about it.
Its best to use separate winding from trafo of 0-15V and get a regulated 12-15V for the driver supply. Peaks upto 4A are normal in occurrence through boot diode when the output is clipping and high side boot cap needs sufficient current pulse to get charged rapidly. A low esr bulk cap is must for driver supply close to boot diode.
And that is what I will do, don't really know why I didn't do it first time around. Having 470u for low and 47u for hi side, its really all about even getting that voltage up to 12 or more volts
 
Nice to hear about it.
Its best to use separate winding from trafo of 0-15V and get a regulated 12-15V for the driver supply. Peaks upto 4A are normal in occurrence through boot diode when the output is clipping and high side boot cap needs sufficient current pulse to get charged rapidly. A low esr bulk cap is must for driver supply close to boot diode.

I found i could get away with a dropper resistor from zero volts and a 12v regulator. The 2092 takes about 125mA when running.
 
what about with zener, big C and smd bypass?

What if you have high voltage rails near +/-85VDC and then the series resistor will have to drop as much as 75V on each side which results in big heat dissipation through resistor and its not a good thing as per my view.;)

Still there are many things which can be improved with this chip such as its current limit, converting feedback to post filter and so on.....
 
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