I have protection against undervoltage, overvoltage (both rails, ~48V) and overcurrent on both output devices.
I have used wire connections to be able to use an unbroken ground plane, hopefully this keeps inductances down compared with a broken ground plane.
I have used wire connections to be able to use an unbroken ground plane, hopefully this keeps inductances down compared with a broken ground plane.
zilog,
I think that if crosspieces to make on the second layer, it not considerably will affect parasitic inductance. But it will be more beautifully and more technologically. 😎
OVP its good! A have only OCP protection...
I think that if crosspieces to make on the second layer, it not considerably will affect parasitic inductance. But it will be more beautifully and more technologically. 😎
OVP its good! A have only OCP protection...

I have 3 different UcDs - a Hypex UcD 180, a Philips Demo PCB, and a home made through hole prototype.
One thing I have discovered is that for short circuit protection when the amplifiers are 'on', but with no input signal present, OVP is essential.
Obviously OCP doesn't really help in this situation, but on all 3 amplifiers the -ve supply goes crazy under short circuit conditions (it pumps more and more negative), and eventually the lower Mosfet will fail. The UcD 180 has been OK, because it has OVP, and my home made one is (mostly) OK now it has OVP, but the Philips board is well and truly dead!!
So, a big 'yes' to OVP IMHO 🙂
One thing I have discovered is that for short circuit protection when the amplifiers are 'on', but with no input signal present, OVP is essential.
Obviously OCP doesn't really help in this situation, but on all 3 amplifiers the -ve supply goes crazy under short circuit conditions (it pumps more and more negative), and eventually the lower Mosfet will fail. The UcD 180 has been OK, because it has OVP, and my home made one is (mostly) OK now it has OVP, but the Philips board is well and truly dead!!
So, a big 'yes' to OVP IMHO 🙂
hi class d from ru . wow i can,t believe i found this forum. i have made this amp using irf540n .at first it used to heat like crazy but i found the solution by changing resistor from 220r to 440r . your amp is powerful will post you pictures of my trials . i never got smd components and irfb fet because of my location will post pictures
hi luka it works fine,silent and very powerful .but i haven,t reached to over +/- 54vlts because of outputfets (i didnt find any bat or 1n58xx diodes so i just used the in4148) the best i can get was irf540n and irf640 they. used to heat insanely at first but when i changed resistor from to 220R to 440R all was fine
i don't have a scope to verify it but it works fine . the fets warm when operating at high volume levels . recently i found these fets irfb23n20 i will try them with +/- 90vlts hope i am in the right track.
i don't have a scope to verify it but it works fine . the fets warm when operating at high volume levels . recently i found these fets irfb23n20 i will try them with +/- 90vlts hope i am in the right track.
hi class d from ru i will upload pictures of my projects once i get hold of a camera thanks
Did you get a hold of a camera? 😀
those resistors are 10x too big... you shouldn't ever need to go above 100Rhi luka it works fine,silent and very powerful .but i haven,t reached to over +/- 54vlts because of outputfets (i didnt find any bat or 1n58xx diodes so i just used the in4148) the best i can get was irf540n and irf640 they. used to heat insanely at first but when i changed resistor from to 220R to 440R all was fine
i don't have a scope to verify it but it works fine . the fets warm when operating at high volume levels . recently i found these fets irfb23n20 i will try them with +/- 90vlts hope i am in the right track.
hi class d from ru ,luka and others here is my project based on this good amp but using non smd components ,totem pole parallel outputs
http://www.diysmps.com/forums/showthread.php?265-2-kwts-discreet-class-d-need-help/page16
http://www.diysmps.com/forums/showthread.php?265-2-kwts-discreet-class-d-need-help/page16
Very nice rendering.
What PCB software are you using? ... maybe I should "upgrade" 😉
Why using IRFP250N? ..... why not just use a single set of IRFB4227 -> less parasitics = less problems ... and they are faster.
What PCB software are you using? ... maybe I should "upgrade" 😉
Why using IRFP250N? ..... why not just use a single set of IRFB4227 -> less parasitics = less problems ... and they are faster.
i'm using eagle 5.1 , also i'm stuck to irfp250n because of availability issues thats the best avail high powerfet for class d here . but i am a bit lucky there is a seller who has added irfb4229 to his stock.i'm planning to use them single +/-75vlts and will parallel 3 pairs for sub channel like +/-90vlts.
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