I have a TPA3255 that I've been using perfectly well for almost 5 years now. A couple weeks ago I decided to upgrade the enclosure and the power supply. Now whenever I try to use the amp (I've tried with multiple power supplies, including the old one and a 3rd one), it plays fine for about 30 seconds at which point the fault light goes on, and about 5 seconds later the clip light comes on and then both lights immediately turn off for a second or two until the Fault light comes on and the cycle starts again. The 3.3v LED also flashes in time with the clip light. I've tested multiple different speakers, line in sources, and volumes, but invariably the board stops functioning after about 30sec of working perfectly.
I've done a thorough inspection of the board, including under the heat sink, and everything looks pristine. I'm currently at a loss for where to go next on troubleshooting/repairing the issue. If I need to replace any components I have the tools (including if I need to replace the TPA chip).
something that may (or may not) be related is that my minidsp 2x4hd that I've been using for the last 5 years also stopped working tonight. I had everything wired identically to how it was before. I'm less concerned with repairing that minidsp since I can easily source an ADAU1701 DSP for $25, but replacing the amp is a much pricier prospect.
Edit: some details I forgot to include: The amp is setup in 2 SE + 1 BTL mode for 2.1 output. The issue occurs on all 3 channels.
I've done a thorough inspection of the board, including under the heat sink, and everything looks pristine. I'm currently at a loss for where to go next on troubleshooting/repairing the issue. If I need to replace any components I have the tools (including if I need to replace the TPA chip).
something that may (or may not) be related is that my minidsp 2x4hd that I've been using for the last 5 years also stopped working tonight. I had everything wired identically to how it was before. I'm less concerned with repairing that minidsp since I can easily source an ADAU1701 DSP for $25, but replacing the amp is a much pricier prospect.
Edit: some details I forgot to include: The amp is setup in 2 SE + 1 BTL mode for 2.1 output. The issue occurs on all 3 channels.
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Bump.
I've gone through all the usual DMM level troubleshooting that I can find on other threads, but nothing is out of the ordinary. I ordered a new IC from TI, and am planning to install it this weekend, but I wanted to give this thread another shot and see if anyone has additional insight before I have to learn how to do SMD soldering.
I've gone through all the usual DMM level troubleshooting that I can find on other threads, but nothing is out of the ordinary. I ordered a new IC from TI, and am planning to install it this weekend, but I wanted to give this thread another shot and see if anyone has additional insight before I have to learn how to do SMD soldering.
I did try a couple different thermal pastes but to no avail.
So I decided to try and replace the chip, but completely borked the install. I think there were some solder bridges between output pins that arced when I turned it on. I think i'll try ordering a new chip (from aliexpress this time, since I don't want to sink that much more money into this board), and if that doesn't work I'll just buy a non-evm board and maybe scavenge parts from the evm.
So I decided to try and replace the chip, but completely borked the install. I think there were some solder bridges between output pins that arced when I turned it on. I think i'll try ordering a new chip (from aliexpress this time, since I don't want to sink that much more money into this board), and if that doesn't work I'll just buy a non-evm board and maybe scavenge parts from the evm.
all 3 voltage regulators are measuring correctly and I've tried it with a range of power supplies.
I ended up buying the new chip, and then learned the hard way that I don't know how to solder SMD components. Got some fun arcs across the output pins, and now its just dead.
As much as I want to try again, I think I need to cut my losses since buying a second chip would put me halfway to a whole new non-evm board. So I'll just find one that's receptive to component upgrades, and pull the bits off the EVM. Or (more likely) let it sit in a junk box for a couple years and then try again to salvage it.
I ended up buying the new chip, and then learned the hard way that I don't know how to solder SMD components. Got some fun arcs across the output pins, and now its just dead.
As much as I want to try again, I think I need to cut my losses since buying a second chip would put me halfway to a whole new non-evm board. So I'll just find one that's receptive to component upgrades, and pull the bits off the EVM. Or (more likely) let it sit in a junk box for a couple years and then try again to salvage it.
I know now what I did wrong (I got impatient and tried to wipe a big bead of solder across the pins instead of individually soldering them), I just don't have any way to confirm that everything else on the board is still fully functional. So I really don't want to sink any more money into this board at the moment. Maybe in a few years when the baby is older, and I am able to get my hands on a proper rework station I'll give it another try