The one I'm trying to identify is D6. It has XH3 9911 on the case. I found an old thread of Perry's that someone responed the package type is SMA / DO-214AC, but I can't seem to find the actual part number for this diode. 🙁
Any help would be greatly appreciated. thx!
Any help would be greatly appreciated. thx!
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Did it fail?
There are two types of diodes used in that part of the circuit. Some designers use a schottky diode. They are low voltage diodes that are fast switching and have low forward voltage drop.
Others use a super-fast or ultra-fast high voltage diode.
The schottky diodes fail virtually always when the outputs and driver IC fail. The high-voltage diodes virtually always survive.
Common high voltage diodes are the ER1D (200v), the ES1G (600v - slightly larger SMB package). The letter suffix indicates the voltage. The MURS and MURA series of diodes should also work.
A common schottky is the MBR0520 (marked B2).
There are two types of diodes used in that part of the circuit. Some designers use a schottky diode. They are low voltage diodes that are fast switching and have low forward voltage drop.
Others use a super-fast or ultra-fast high voltage diode.
The schottky diodes fail virtually always when the outputs and driver IC fail. The high-voltage diodes virtually always survive.
Common high voltage diodes are the ER1D (200v), the ES1G (600v - slightly larger SMB package). The letter suffix indicates the voltage. The MURS and MURA series of diodes should also work.
A common schottky is the MBR0520 (marked B2).
yes, iuts shorted. In diode check I get 0.000 in both directions.
So, what version should I be replacing this one with?
So, what version should I be replacing this one with?
Was the diode off of the board when you checked it?
If so, remove one of the remaining (good) diodes and check it. What is the forward voltage when checking it with the meter set to diode-check.
If so, remove one of the remaining (good) diodes and check it. What is the forward voltage when checking it with the meter set to diode-check.
They were still in the circuit. I removed 2, one good one bad. Bad still reads shorted. The good one has a forward voltage of .408v
That appears to be a standard (non-schottky) diode. Do you have any of the diodes I mentioned on hand?
When you replace the diode and get the amp working, you should compare the voltage across the ceramic high-side capacitor for each driver IC. They should have about the same DC voltage across them.
When you replace the diode and get the amp working, you should compare the voltage across the ceramic high-side capacitor for each driver IC. They should have about the same DC voltage across them.
No I don't. I could possibly pull one from my Atomics driver card, but not sure if they are the same. I'll look to see which ones are on it when I get home. Thx Perry
It would be good if you use something that you know the part number so that you can use it in the future.
Which ones worked for you Cory? Is it better to go with the 600v version (ES1G)? This is in a American Bass 1100.1
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It wouldn't hurt to use the 600v rated part. The AB1100.1 is just two 5k's internally strapped, correct?
Wonder why that diode failed. thats the charge-pump diode for driving the high side MOSFETS? if that fails, it would almost certainly mean failed/destruction of the IC and/or the high side mosfets.
I think the diode is the last thing to fail. It's likely that either the IC or the outputs fail and when that happens the diode fails.
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