Question about optimizing PFFB for TPA3245

Oh that is very frustrating. At first I would apply some liquid flux and desolder -
there is a chance that the (invisible) shorting blob will disappear.
If this does not help - I would apply some solder again at the pin
and then desolder with the help of flux.
Which resistance do you measure between pins?
 
Have a look here
https://www.mouser.de/datasheet/2/447/F3294_MMK-3316041.pdf
1uF/MMK5 with a series resonant frequency close to 2MHz
corresponding to about 10nH series inductance
There are better options as well
https://www.mouser.de/datasheet/2/447/KEM_F3101_R82-3316969.pdf


Unfortunately, Kemet openly states that capacitors in this series may use either wound or stacked film technology. I still prefer WIMA, simply because it gives me certainty regarding the internal construction.


Well, I need MKS2 capacitors in the following values: 3.3 µF / 50 V, 1 µF / 63 V, and 330 nF / 63 V, as well as an MKP2 in 220 nF / 100 V. I’ve already bought a small stock of them from Reichelt, since Mouser has recently started flagging these parts as restricted for shipment to my location.

Now, only the 330 nF / 63 V MKS2 remains to be sourced. All capacitors are with ±5% tolerance.
 
0.2Ω - effectively a dead short. The solder joints have been carefully inspected under a magnifying glass. The PCB layout clearly shows that the traces connected to these pads are entirely external to the IC package. The board design makes it impossible for the short to exist anywhere else — the only logical conclusion is that the short is internal, between pins under the IC body.

It’s a shame that Kester TSF-6502 flux is hard to source off the shelf these days. Maybe RMA-7 will be sufficient and provide adequate surface tension reduction for leaded solder.


I need to invest in a hot-air rework station — it would be a shame to ruin the PCB by desoldering it the hard way.
 
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Found it — it was a tiny short. A brand-new and ‘dry’ tip (never used) helped. Unfortunately, the flux I had on hand — RMA-223 (the only one available locally without waiting for shipping or courier) — isn’t really great for SMD work. But hey, now it's time to enjoy some music.

Actually, I guess my neighbors are enjoying some good music too, whether they want to or not 😉

Cheers!
 
And btw, although I have a hot air station I do not use it to desolder TPA3118. Instead I flood all pins with loads of solder,
keep it all liquid using one or two big solder tips and then lift the chip. No damages to pads. Pre-warming from the bottom side may ease things, but I do not have a heating plate. Some of my TPAs have been soldered/desoldered several times and still work.