The mosfets being used, the IRS2092 chip, and the caps are all rated for 100V. Has anyone run one of these close to +-100V (lets say 90) for any extended amount of time?
Also, as cheap as these boards are, a relay circuit would cost as much as the amp board... and if the amp board does fry itself, it's advised to replace the IRS2092S chip along with the mostfets. So... at $15 a board, it's a better idea to just pitch it vs fixing.
Peavey used a Triac to crowbar the output to ground on the CS800 and other power amps. This seems to be maybe a good cheap solution to save expensive speakers from damage??
Also, as cheap as these boards are, a relay circuit would cost as much as the amp board... and if the amp board does fry itself, it's advised to replace the IRS2092S chip along with the mostfets. So... at $15 a board, it's a better idea to just pitch it vs fixing.
Peavey used a Triac to crowbar the output to ground on the CS800 and other power amps. This seems to be maybe a good cheap solution to save expensive speakers from damage??
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I will add for others that I have this running at +-75 VDC (bi polar supply) and the inductor gets pretty hot to the touch. The heat sink isn't too bad. It's loud and very clear sounding.
I'm probably going to add a crowbar type circuit at the end of this thing. Several good amplifiers do this. The downside that those designs (Peavey PA amps, McIntosh MA6100, Quad 405, etc) had is that it takes out the power transistors during a failure. In this case, if there's a failure, it's probably good to have the speaker terminals crowbarred, since most likely the mosfets and chip are trash as it stands. Best to protect the speakers and the triac setup is cheap and effective.
BTW, Here's the eval board schematic (which this is supposedly a loose copy of). Note the different output devices vs the pair of individual MOSFETS on the china unit and I'm sure several other differences, but this is at least a start as far as a schematic to compare to.
I'm probably going to add a crowbar type circuit at the end of this thing. Several good amplifiers do this. The downside that those designs (Peavey PA amps, McIntosh MA6100, Quad 405, etc) had is that it takes out the power transistors during a failure. In this case, if there's a failure, it's probably good to have the speaker terminals crowbarred, since most likely the mosfets and chip are trash as it stands. Best to protect the speakers and the triac setup is cheap and effective.
BTW, Here's the eval board schematic (which this is supposedly a loose copy of). Note the different output devices vs the pair of individual MOSFETS on the china unit and I'm sure several other differences, but this is at least a start as far as a schematic to compare to.
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Have you also examined MOSFETs used on this board? They are 99% fake IRFB31N20D, sometimes rarely IRFB4019, etc for example. The parameters are 2-3x worse than that of genuine MOSFETs. Worst seem to be IRFB31N20, miraculously this modules somehow works, if you don't push it too far, it even works quite normally. All modules I have looked at contain fake MOSFETs which in many cases behave like Logic Level MOSFETs, therefore probably the IRS2092 itself is also a weak-fake and would not be able to handle for example, genuine IRFB4227 or modern SUP MOSFETs without buffer stage. Apparently, if IRS2092 of these modules is also not genuine Infineon version, but some CSC3120, YD7120, etc., simply rebranded as IR2092. It could be quite interesting to replace it with a known OEM genuine chip and better MOSFETs.
Supply voltage cannot be taken very high because of the DC-DC converter IC on board, its maximum input voltage was about 80 volts.
Supply voltage cannot be taken very high because of the DC-DC converter IC on board, its maximum input voltage was about 80 volts.
it is possible do make a picture from this board without heatsink?
what the way to the voltages use for the IRS2092?
if Zener used, it's nessary to check the resistors and zener to pervent thermal disaster
edit:
pictures found
https://www.diyaudio.com/community/threads/ebay-amp-is-500w-believable.309168/
what the way to the voltages use for the IRS2092?
if Zener used, it's nessary to check the resistors and zener to pervent thermal disaster
edit:
pictures found
https://www.diyaudio.com/community/threads/ebay-amp-is-500w-believable.309168/
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