JX500/1D driver IC

I have a broken JL JX500/1D with a busted power supply. I have only taken time to identify the issue, I assume this is the driver IC for the FETS, they don't cross to any thing either. I can't cross this device M18021HN. There is a missing section of the IC that starts MPS. There a 4 power supply transistors, two are burned. Any Ideas? I have added attachment with picture.


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Hello, I have the same issue regarding identifying a replacement for this same chip, M18021. To my understanding, XXT460 (is) are the power transistors. Pls, if anybody has abled to get a cross reference to the above (IC3) I'd really appreciate it.Thanks again.
I ordered chip from http://www.mouser.com/ . I had no luck repairing this amp. It ran for a few minutes and crashed again. I put it up to revisit. I replaced with an MP18021HN. The manufacturer suggests bottom tab be soldered for proper heat dissipation and it it soldered to the board. I may have damaged chip upon installation. As I remember the opposite side of the board has transformer mounted over the IC. I would be interested in any info from anyone having made a successful repair.

Re: MP18021HN (JX500/1D)

Thanks for the reply. No wonder I could not find informations about that IC
of my own typo. I used to work as an electronic tech and performed my own rework on circuit boards. Yes, i wondered about such a high current component's underside cavity wasn't soldered at all the which it was supposed to. I looked all over the internet for this part and every authorized dealer were out of stock. Yesterday, i made contacts at Alibaba.com in China and made some orders. Im hoping that I wont get some fake-*** parts like i experienced once in Ebay from a Chinaman. From the look of the circuitry, this car amp is the the most complicated-looking thing compared to other brands that ive worked on before. Im disappointed that JL would not provide/sell me the schematics. This is why I stayed with Soundstream and Fosgates old schools stuff coz they provide free schematics.
Btw, do you have a schematic for this JX model? id like to get a copy if you dont mind. Thanks.
Possible mod for JX500

This burning of the two power transistors can be prevented from spreading by
cutting the Drain/ or Source's pin open and install in-line fuses in between. I just remembered that they do this on Rockford Fosgates non-HD punch 45/75/150 series amps.
I do not have a schematic for this amp, I wish I did. You can get the pin out of the IC and sketch your own. You probably recognized the basic power supply design so there's a start. Usually you can install the driver chip and transistors without the power FETs and see the signal on the scope. This doesn't work on this amp, I did replace the oscillator chip. Probably a way to force it on, but I didn't get that far.
I've got another one coming in with a bad output section, I'll have some reference at that point. This is just a hobby now, so when I get up a a half a dozen amps or so I make a little time to work on them and sometimes, one like this, gets put back until I get interested again. If I remedy it I will post what I learned.
If anyone is still monitoring this I am pretty sure I've crossed this IC out to be able to use a Texas Instruments UCC27201A Driver - it seems to be viable - attached are the two screenshots from the data sheets if anyone wants to check behind me.


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