Baltistyle

If these sources do not list the chip, its generally not commercially available. If it will become available or has ever been in their stock, there is an estimate to production which is generally reliable. If there is no history on those sites, your only option will be alibaba or the like.

Your last option would be to get another blown amp and replace the chip with one that is not burned for the same reason.

Left Coast Geek

I couldn't find anything on ST's own site with a part number even remotely like any of the numbers on that chip, at least not under either A-B or Class D amplifiers. They area all TDAxxx or SDAxxx.

CaliBenzDriver

For the HKL Amp records...
the MY'15 amplifier module in this thread has no available spares ... so far 🤞
We can guess, it's a custom chip by ST. It is recognized to integrate ALL amplifiers (main+woof)


module tag


Overall PCB


But MY'14 and priors with independent woofer module has available ST spares and known to be serviceable.


prior design ✌️

This way you can easily sight chances of repairs without dismantling your W212.

Left Coast Geek

here's a typical ST automotive digital input quad power amp that comes in the SO36 package similar to the ones shown.
https://www.st.com/resource/en/datasheet/tda7801.pdf

specs are in about the right range for what I'd expect from the HK7 system.

but nothing on the chip we were shown looks like "TDA7801PD" (which is this chip in the SO36 package)

CaliBenzDriver

It's possible to cross reference this amp to a compatible chip by studying the published pinouts of the matching ST product lineup.

There's also a chance the suspect module is still okay because ST emphasizis on self-protection...

Just clean the brownish PCB and compare values with next similar amp over. Probe at the pins. Expect the PCB via to be "shorted open".

Cost-free 😎

Left Coast Geek

these amps are pretty complex, and have programmability over their serial data communications bus. there's a dozen different base models, i'm not sure a simple pin comparision would suffice.
oh fun. Mouser lists the TDA7801PD ... minimum order 310, for $9.87 each, extended price $3057, FIFTY TWO WEEK LEAD TIME.

estore.st.com will sell you 1 for $13, but says "OUT OF STOCK"