Marketing lies from china. A linear power supply is inherently never a switching power supply (SMPS). They'll never be that small.
An Astron would be an example of something that could work.
An Astron would be an example of something that could work.
Hello friends, has any of you experienced malfunction with eBay chip fed with ~15V? I think mine stopped working after I hooked it up with an SMPS that's supplying 15V. When I turned it on, there is random pop and noise from the speaker, and a little burn smell, also the heatsink got really warm within that 4-5 seconds, warmer than if I had it playing for a day. I let it sit for about an hour and tried again, LED is still on, I can confirm signal and power is coming to the board and polarity is correct, but no sound and the heatsink is dead cold. As if the chip is not working. It may be obvious but is it really the chip that has gone kaput or should I look elsewhere?
Thanks!! ��
Thanks!! ��
Many eBay sellers now state 12v, since they fail so damn easy with more... They're reject chips, it's not a surprise.
So those symptoms, combined with the fact that they are rejects, concluded the chip needs to be replaced? Is there anything else I need to check in the circuit? Thanks.
No, as long as polarity is correct, and the outputs are isolated from the rest of the amp, it's probably just too much voltage for the chip.
So it's dead? No protection mode or something that mutes it temporarily? I was wondering.
Also is there a measuring I can do to check if the chip is still working?
https://www.tokopedia.com/suryaelectronics/tda7297
Does that look legit? The packing is different. Thanks so much for your kind assistance.
Check? Play music, and check the outputs.
It has lots of very good protections built into it. It's one of the best there is for that, IMO. But it can't protect from over voltage. Over voltage will fry anything that can't handle it.
It has lots of very good protections built into it. It's one of the best there is for that, IMO. But it can't protect from over voltage. Over voltage will fry anything that can't handle it.
15 volts?
J:
Why would you run 15vdc rather than the 12 volts which is recommended?
If your car calls for 5 quarts of oil would you put in 3 and expect it to perform properly?
MW
J:
Why would you run 15vdc rather than the 12 volts which is recommended?
If your car calls for 5 quarts of oil would you put in 3 and expect it to perform properly?
MW
Because the datasheet says it's good to 18v.
A good chip you order from Mouser or Digikey can take 23v for an unknown time (at least a week). Where as the reject chips that come on the chinese boards struggle above 12v.
A good chip you order from Mouser or Digikey can take 23v for an unknown time (at least a week). Where as the reject chips that come on the chinese boards struggle above 12v.
@Mark: What Jeremy said. Also my SMPS is 12V with a trimpot to adjust output VDC, I didn't realize it was operating at 15V and that it can kill the chip. Honest mistake here. Anyway replacement chip is on the way.
I've been running mine on 19V from a SMPS for ages and it a'int failed yet, didn't get more than mildly warm to the touch either.
What more do want for a couple of quid?
What more do want for a couple of quid?
Come to think about it, it could be this: I made a capacitor bank, one from brand new original Panasonic caps, one from removed caps off eBay boards. All 1000uF/35V. I thought it wouldn't hurt to compare if there is any difference in sound among the two. My SMPS is fairly good, I have been using it for 6 months or so, solid performance, with only few mV of AC in the ouput, so the eBay caps in parallel should help, that was my logic. Could it be 7 of them in parallel messed up the power so bad that it fried the chip?
I ran my amp at 15V for 2 years and one day it just stopped working.
But who knows, the same scenario could have played out if I'd run it at 12V too. 😀
But who knows, the same scenario could have played out if I'd run it at 12V too. 😀
What I have found with all three of the boards I purchased is varying levels of soldering quality.
Two of them had the electrolytic capacitor so badly soldered that they all but fell out with little effort on my part and the connectors were the same on one board.
Having discovered that I simply resoldered everything, if I'm honest I thought I detected lower noise levels after and as said before none have failed yet.
Two of them had the electrolytic capacitor so badly soldered that they all but fell out with little effort on my part and the connectors were the same on one board.
Having discovered that I simply resoldered everything, if I'm honest I thought I detected lower noise levels after and as said before none have failed yet.
I have bought several of the green boards with larger plain aluminum heatsinks. They have all worked well and seemed decently made - for $5 cannot complain. They work at 19v but mine are extremely hot to touch if using 19v so I use 12v and don't have any problem with that. When using the OS Destroyer PCB though, the regulator is set for about 18v and the thing definitely needs a bigger heatsink. I do not understand why quality level of board would make it run cooler or hotter? Waste heat is simply current x voltage drop. Could some boards have a higher quiescent bias setting?