The transformer is the weakest point just as I assumed. Normally it is the most expensive part in a PSU so that is where money can be lost. Or gained... It is not the fault of Aliexpress but it is the seller at fault. A careful examination of the pictures made me conclude the findings I stated earlier. The board itself is fine. Not everyone in the world can build safe and well built stuff. It is better to be a critical customer and not let a low price fool you.
Let a friend with mobile phone make a video and get your money back. Stuff like this should not be sold!
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Did I say otherwise? I didn't say you should use expensive film caps for power supplies decoupling, but I do not trust tantalum types. Once I had an Asus motherboard where tantalums caught fire! Same thing happened on a pair of signal input tantalums on a preamp.
However, some capacitor types, like low ESR electrolytics, do not like certain places on a supply or with some regulators.
Agreed on the X7R and Z5U should just be used on power supplies decoupling, but I doubt any ceramic type, even COG or NPO, can equal the audio quality of a good film type, particularly polystyrene if you can find it, or polypropylenes. Sometime I may try them and change my opinion.
Polystyrenes are the best for audio signal filtering, and nothing else.
Tantalum capacitors were unreliable long ago. Nowadays every mobile phone has them. The technology has improved a lot. The bad reputation comes from the so called drop types. These were notorious for catching fire, especially when used directly on power rails. It is still advisable to derate tantalums i.e. to use a 35V type in a circuit where voltage will never be higher than 25V. 20 Years ago I would not touch them except when I replaced them for normal electrolytic caps, nowadays I am quite fond of them because of their excellent specifications.They are one of the few that have values with different ESR variations. So 47 µF 25V in let's say 50 mOhm but also in 100 mOhm ESR version.
The mining of the coltan ore is in many dubious countries though. It is a fact that countries paid for weapons with coltan. I am not aware what the situation is now. Considering the fact that mobile phones are produced in extreme numbers I guess the situation must have changed. Or...
Polystyrene caps are hard to find and they were quite fragile and moist sensitive. Hardly a cap to advise to others as production was stopped long ago just like that of the excellent MKC caps.
Back to LT3042...there are way too many threads about capacitors.
LT3042 and LT3045 were introduced recently while LM317 is a design from 30 years ago (or more). Then low ESR caps did not exist ! It is a bit sour that at the end of the analog era the best regulators are invented
Recent regulators are almost all of the LDO type and the ability to withstand the now standard low ESR ceramic caps is incorporated in their design. The industry and the customers like ceramic caps because of their small size and price so that is what becomes standar and that is why attention went to improving those. Modern ceramic caps do not resemble the old disc type caps.
The mining of the coltan ore is in many dubious countries though. It is a fact that countries paid for weapons with coltan. I am not aware what the situation is now. Considering the fact that mobile phones are produced in extreme numbers I guess the situation must have changed. Or...
Polystyrene caps are hard to find and they were quite fragile and moist sensitive. Hardly a cap to advise to others as production was stopped long ago just like that of the excellent MKC caps.
Back to LT3042...there are way too many threads about capacitors.
LT3042 and LT3045 were introduced recently while LM317 is a design from 30 years ago (or more). Then low ESR caps did not exist ! It is a bit sour that at the end of the analog era the best regulators are invented
Recent regulators are almost all of the LDO type and the ability to withstand the now standard low ESR ceramic caps is incorporated in their design. The industry and the customers like ceramic caps because of their small size and price so that is what becomes standar and that is why attention went to improving those. Modern ceramic caps do not resemble the old disc type caps.
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Hi I have connected Vin Vout and GND
All the components seem to be on the board, but it is not working
should i connect any additional pins?
Hi, regarding the cheap Chinese LT3042 board in this thread. I used to use the same LT regulator boards but ran into some issues with a few of them recently. Apparently fast start up resistors are omitted resulting in a very slow ramp up time of many seconds (depends on value of Cset). This caused trouble in a DAC with the XO. I also had one where one of the diodes became a short. A few 11DQ10 and a new filter cap are a minimum when the slow ramp up time can be tolerated. The connectors are ferro material. I ended up removing the LT3042 and reused them on new boards.
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Some regulators work better with a flat impedance curve, like what a tantalum part will give. I think I actually recall a data sheet that specifically mentioned the use of them.
And just because a regulator data sheet will suggest the ceramic parts, that may more be to entice users of mass volumes of parts. Sometimes other parts will improve things.
I don’t have much experience with the lt3042, had one of the popular dual boards but it wasn’t as ldo as purported, and it wound up in the bin.
And just because a regulator data sheet will suggest the ceramic parts, that may more be to entice users of mass volumes of parts. Sometimes other parts will improve things.
I don’t have much experience with the lt3042, had one of the popular dual boards but it wasn’t as ldo as purported, and it wound up in the bin.
Sorry to insist, but can you draw your mod on the schematic? I would like to try this mod on my 3042 LTSpice sim. See what it changes.
Datasheet…. “Fast start up” is not a mod but a necessary feature when using larger values for Cset. The Chinese board uses a large value cap for Cset but they forgot to implement "fast start up".
Unfortunately LT3042 performs best (least noise) with large value like 4.7 uF for Cset. Not all devices have problems with a slow ramp up. Another solution is to replace Cset for a 1 uF type at the expense of somewhat higher noise that will still be below 5 µV. I did the latter on other boards.
Unfortunately LT3042 performs best (least noise) with large value like 4.7 uF for Cset. Not all devices have problems with a slow ramp up. Another solution is to replace Cset for a 1 uF type at the expense of somewhat higher noise that will still be below 5 µV. I did the latter on other boards.
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