question :post filter feedback

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Well an IR2110 can do 3.5A output and that is most certainly what is needed with six fets as the gate capacitance have increased with four.

A 7812 cannot do mutch more than about 1A so that may be the problem, try with a 12v smps instead if you got one and hook it up where the voltage reg was.
 
Fredos:
HI ...
do i have to use the tantalum material with bootstrap capacitor ??

does the 22pF and 100ohms serial or parallel over the coil??

Thanks ....

Tekko :
If we need to use more six fets , what i have to do to driver so many fets with ir2110 ???
can i add additional driver circuit to driver the fets ???
 
I'm using IR2112 with three pairs of IGBTs, each one with its own pair of buffer transistors. My supply and bootstrap capacitors are just 2.2uF high ESR electrolytics with 100nF ceramic in parallel, yet the system behaves flawless when clipping a 50Hz sine wave (or any frequency, since maximum and minimum duty cycles are controlled to ensure proper bootstrap capacitor charge and avoid subharmonics).

So don't rush to blame gate drive...
 
Eva:
Does the driver like the picture i post ???
 

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Yes, my circuit looks like that. I need the buffers because IR2112 is limited to +/-200mA. Also, R33 is intended to prevent parasitistic gate turn-on at startup and at power down, but it's really not required because IR ICs seem to be already designed to behave properly on these situations. On the other hand it will increase bootstrap capacitor requirements considerably as it imposes a DC current consumption much higher than the one from the IC.
 
Fredos :
I have tried increase the bootstrape capacitor to 80uF.
But seems get too much turn on power ripple to turn on the DC protection circuit.
I decrease to 60uF , It can turn on success.
But Still can't get clip to +/- RAIL...

I scare it cause by my power supply can't get so much power i need , when i want to get 400Wrms.
I will test the +/- RAIL , when i want to get more power.
 
I have tried with the speaker , And Yes , when i want to get more power output.
The +/- RAIL get down a little.
And let me don't get the amplitude i want to get.

But when the output waveform get clip , It still get crackle sound.
And the DC proctect get working to shunt down the SMPS power.

So, doesn't anyone use the DC proctect ?????
 
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