The most probably it's about "inrush current". An NTC(thermistor) inside the power adapter will solve that.
The most probably it's about "inrush current". An NTC(thermistor) inside the power adapter will solve that.
So we did not rule out the possibility of adapter failure causing all this. And when we call back defect units, we will ask our users to send back whole set including power adapter.
Good response from Topping, finally.
I would really like to see possibility of firmware upgrade kit with new microcontroller, or a replacement board which can either be cross-shipped or paid for at cost by certified owners (on proof of purchase). Soldering the QFN package is possible by visit to PC technician. I would really like to see a fix for disabling the 0dB mode from remote without a second press or some kind of confirmation. That is my big issue, since I am connected to very loud speakers and have some consideration for neighbors.
Now my unit has never actually had this standby issue (knock on wood). Mine is a very early production unit - 1808xxx, runs off a very basic linear supply and has never been connected to Windows except for initial testing, which is also the only time the included power supply was ever used. It means I have never had the XMOS update released by Topping. It has also been connected to a pair of headphones exactly once. However sometimes the display will go off when the source powers down. Pressing power button awakens it.
I doubt adapter has anything to do with this. There have been multiple users here who purchased mean well aftermarket power supply to test out if it helps out, and I believe nothing has changed.
My issue is a bit different than the one you are talking about, but I feel it is connected somehow: my unit goes into suspend mode by itself every once in a while (every 2-3 weeks), happened exactly 4 times since I purchased it. I have no issues with waking it up by pressing power on button (so far). Few weeks ago I bought mean well GS25A15-P1J (15V 1.66A power adapter) and exactly 2 days ago experienced another self-shutdown. So in my case changing power supply did not help.
It is a pity that 15v are used here, not 12v. There are a lot of good 12v psu and easy to find. But where to get a good 15v psu?
TP-Wong, any lead as to why the units could randomly enter standby mode ? Not being able to get out of standby is something, but for most people it's just shutting down it.
This is what we are considering. More and more things were done by MCU, but firmware of our MCU is not able to update, this is a potential risk.
Hi
I can get a new chip soldered. More advanced users will be able to program it using USB-I2C using the onboard header if you provide the code to access the MCU - but I think that's too advanced, so maybe just sending replacement chip with instructions on removing and replacing it. Not a very difficult job, any tech with a hot air station and good hands can do it in about 5 minutes, and it's cheaper than sending the whole unit back to factory.
Good Luck. The DX3 is a good sounding unit in spite for few basic mistakes in design and is a good deal at the price. Maybe next time get a good analog designer for the output stage, or ask AKM to lend a hand. The pop noise can quite easily be cured, so the relay activation won't be as much of a problem.
Re 12V - it should be fine and put little less strain on the regulators, but there might not be enough headroom for the 10V rails. 13V or greater should be fine as most regs are fine with 3V across them. I have my LPS set to 14V and it works great.
TP-Wong, did you change the capacitors type at some point ? Maybe another one with lower ESR ? I was add two capacitors of 220uf/10v with ESR=0.14ohm in the analog power supply and....bang. Never could start without a voltage source with over 2.6 Amps. So, probably the cause is an over-current somewhere.
Most users that reported completely dead units were using < 40 ohm headphones. If I'm not wrong, testing the unit with low impedance might be worth the shot.Over current, should be one possibility lead to defect: Over current somewhere>>>>Over load or over heat of TPS54331>>>>Dead.
Could you reveal a little more info about P50 - release date, price range? It could be really interesting LPS.We did not do long test for DX3 Pro working on DC12V so I'm not sure it is suitable or not. But sure it works well with our LPS P50 which is coming soon, same size with D50 but double height of it, providing 1xDC15V, 2xDC5V output. We bring the P50+DX3 Pro combination to Canjam Shanghai for show last year.