pls help...using gate driver in class D amp

[winky4110]

wish someone pro can help me....
i m doing a class D amplifier for subwoofer but facing problem in using the gate driver..,i hv tried to use ir2011 n hip4081 but fail. i decided to build an half bridge amp, using +-24v supply. switching frequency is 130khz. mosfet is irfb4212. any recommended gate driver n how to test it?

 

[darkfenriz]

Nothing wrong with gate drivers you've mentioned.
There may be numerous reasons why design's failed, none will guess.

 

[winky4110]

thx for ur reply....
in the attachment is wat i do...but the result is....short circuit....
i don't know wher is the error...T.T

 

[darkfenriz]

One obvious thing is that lower side drain must connect to Vs nd higher side source.

 

[winky4110]

u mean there is no problem with tis connection? so if i short the drain of the lower side to the source of the higher side, tis circuit should b working? how to test the circuit so i can confirm it is working? if i connect anode of the oscilloscope to HO, n cathode to Vs, should it b a pulse signal tat similar to the signal of HIN? and the signal of LO and COM should b similar to the signal of LIN? is the dead time for tis circuit sufficient?
Thx a lot!!!!

 

[winky4110]

is the schematic wrong? any recommendation??

 

[81bas]

u mean there is no problem with tis connection? so if i short the drain of the lower side to the source of the higher side, tis circuit should b working?

yes, this should work in this way

how to test the circuit so i can confirm it is working? if i connect anode of the oscilloscope to HO, n cathode to Vs, should it b a pulse signal tat similar to the signal of HIN? and the signal of LO and COM should b similar to the signal of LIN?

yes, something like this Make sure, that you always produce the LIN pulse first, before producing HIN pulse, since the high side driver is supplied by bootstrap capacitor (the 330nf one), which is charged during the LIN pulse...

is the dead time for tis circuit sufficient?

it is needed to know the driver IC and mosfet types first. And then it is needed to know how you will produce the HIN and LIN pulses...

 

[odnaizutra]

try to google how half bridge work , and you will have some lights .
Please refer to irf reference designs like iraudamp 1 just to have some basic

 

[winky4110]

dun connect anode of the oscilloscope to HO, n cathode to Vs, i had spoilt many ic by tis way n finally only i realised tat(IR2011). so finally the amplifier was completed. thx all of u!!!!