That's bad luck! While I haven't used the L25D boards myself, I've blown up and then fixed a couple of L15D's, and I believe the basic circuitry is very similar.
If there's high voltage at output, I would immediately suspect that either or both IRFB4020 MOSFETs are blown. Pretty easy to check, just put a meter across them and check whether they're shorted
The other transistor on the heatsink may have blown too, and depending on what caused the fault, the surface mounted IRS2092 chip on the underside of the board as well.
To be on the safe side, I'd replace all of those components (they're pretty cheap and readily available - I bought a few spares from Aliexpress just in case), and also check all the other semiconductors too (i.e. diodes and zeners).
Then, before powering up again, you need to determine what caused the fault in the first place. Could be a speaker short, or too low impedance speakers (I believe the L25D's don't like much below 8 ohms), or a wiring, connection or soldering problem on the board. Or possibly no heat transfer compound between the transistors and the heatsink, causing the MOSFETs to overheat - I've heard this is not uncommon in pre-assembled boards, and might explain why it worked for a while before failing.
If you didn't assemble the board yourself, I'd also check (and reflow) all solder joints (the solder joints on pre-assembled boards I've had weren't great quality which is why I prefer to assemble them myself). And I'd double check that all components are correct and in the correct places.
When I first blew up an L15D (my own fault for not checking speaker shorts before switching on!), I ordered another one as a spare, plus MOSFETS, transistor and IRS2092 components to fix the blown one. That means I now always have a spare working board, so if I have a a blow-up in the future, I can just swap out the faulty board and fix it in my own time.
Hope this helps and it all works out.
Cheers,
Jon.
If there's high voltage at output, I would immediately suspect that either or both IRFB4020 MOSFETs are blown. Pretty easy to check, just put a meter across them and check whether they're shorted
The other transistor on the heatsink may have blown too, and depending on what caused the fault, the surface mounted IRS2092 chip on the underside of the board as well.
To be on the safe side, I'd replace all of those components (they're pretty cheap and readily available - I bought a few spares from Aliexpress just in case), and also check all the other semiconductors too (i.e. diodes and zeners).
Then, before powering up again, you need to determine what caused the fault in the first place. Could be a speaker short, or too low impedance speakers (I believe the L25D's don't like much below 8 ohms), or a wiring, connection or soldering problem on the board. Or possibly no heat transfer compound between the transistors and the heatsink, causing the MOSFETs to overheat - I've heard this is not uncommon in pre-assembled boards, and might explain why it worked for a while before failing.
If you didn't assemble the board yourself, I'd also check (and reflow) all solder joints (the solder joints on pre-assembled boards I've had weren't great quality which is why I prefer to assemble them myself). And I'd double check that all components are correct and in the correct places.
When I first blew up an L15D (my own fault for not checking speaker shorts before switching on!), I ordered another one as a spare, plus MOSFETS, transistor and IRS2092 components to fix the blown one. That means I now always have a spare working board, so if I have a a blow-up in the future, I can just swap out the faulty board and fix it in my own time.
Hope this helps and it all works out.
Cheers,
Jon.
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Hi everyone, I bought two l20d to drive a subwoofer, where each module will drive a double coil loudspeaker. With the coils connected in series. The impedance is of 6.5 ohms. Having to chose the feeding voltage of the SMPS, according to you, which one should I prefer? 60 or 72 volts? The SMPS will probably be Connex SMPS800RE.
Many thanks,
Gaetano.
Many thanks,
Gaetano.
I'm sorry to have to post this but I think buyers should be aware of my experience in the last couple of weeks with Connex, I have sent them emails regarding info of the aux pin-outs on both amp and smps and they just don't reply or they say that my emails go to their spam, their products are good but if you have any problems you are on your own.
I managed to buy a single L20D from ebay.
The setup where it was assembled has been working solid to power a 250W RMS speaker.
please can you show us a pic of the board. i found different version (e.g. V7..etc.) in the net
thx chris
sorry for hijacking if not related, any suggestion about this kit for 12" 4ohm subwoofer? I'll be using dual 40Vac 500VA for 2 stereo boards
US $40.98 | YJ IRS2092+IRFB23N15D 700W 4ohm Mono Class D + Speaker protected+Double rectification Completed Amplifier board
AliExpress
US $40.98 | YJ IRS2092+IRFB23N15D 700W 4ohm Mono Class D + Speaker protected+Double rectification Completed Amplifier board
AliExpress
Hi again I have 4 L20d amps 2 working and 2 not, I have changed the fake D669 transistors and IRFI4020h and IRS2092 ic with genuine ones and checked voltages which look good but they just wont start, the led doesn't light up, anybody got any clues as to why?
hi
nigel is normally one expert at this IRS2092 boards. i read that if the FET are gone "normally" they take the IRS2092 chip too !!... so check if the chip is sane.
chris
sorry for hijacking if not related, any suggestion about this kit for 12" 4ohm subwoofer? I'll be using dual 40Vac 500VA for 2 stereo boards
US $40.98 | YJ IRS2092+IRFB23N15D 700W 4ohm Mono Class D + Speaker protected+Double rectification Completed Amplifier board
AliExpress
Hi
i haven´t this board or another irs2092 board but i have 2x 12" sub (open baffle 8R). i hope you really need this power
as i look at this board its with PSU included and the rated power is that what you are searching for.
40V AC rectified is about 60V so its ok for the MOSFETs (IRFB23N15D-older versions) = 150V Vds and 23Amps
chekc which operating frequency is used at this board and try to keep that accoridn to the datsheet (irs2092 -IRAUDAMP...)
what i read is that the imput impdance is normaly low so you have to look at your source to "drive" this input. here is written thats 14kR but i rememeber about 9k.
2cent: i personally do not understand why the heatsink is always at these boards not like the fans are let the air flow up...but its cheaper to slice the heatsink like this i guess
chris
hi
nigel is normally one expert at this IRS2092 boards. i read that if the FET are gone "normally" they take the IRS2092 chip too !!... so check if the chip is sane.
chris
I often found the 2092 was taken out when the mosfets blew.
As mine were in sockets it was easy to change it at the same time.
If the gate/drain on the mosfet blows it shorts 2092 outputs to b+ and takes out the 2092.
After changing blown mosfets then finding they blew again I just changed 2092 as a matter of course each time.
Hi again I have 4 L20d amps 2 working and 2 not, I have changed the fake D669 transistors and IRFI4020h and IRS2092 ic with genuine ones and checked voltages which look good but they just wont start, the led doesn't light up, anybody got any clues as to why?
L20D = IRAUDAMP7D-200
It's very simple. I've never seen any damage.
Hi everyone, I bought two l20d to drive a subwoofer, where each module will drive a double coil loudspeaker. With the coils connected in series. The impedance is of 6.5 ohms. Having to chose the feeding voltage of the SMPS, according to you, which one should I prefer? 60 or 72 volts? The SMPS will probably be Connex SMPS800RE.
Many thanks,
Gaetano.
I suggest you use a circular transformer.
It's more reliable.
There may be no problem with switching power supply. There may also be problems.
It's even so bad that it damages your equipment.
AC 50-0-50 300VA
I managed to buy a single L20D from ebay.
The setup where it was assembled has been working solid to power a 250W RMS speaker.
I have to correct a wrong concept.
The trumpet we use. Marked power. It is not the same as amplifier power.
For example, 250W trumpet. In fact, in the case of household use. The required power is only 5 watts.
In most cases. I prefer L15D.
Believe me. The power of the speaker doesn't make any sense.
In fact, the power of the power amplifier is equally meaningless.
If you need more volume. So what you need is one. P7MINI similar preamplifier.
It's not a higher power amplifier.
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