I have some other LT1963+LT3015 regulators with identical components on both LDO. And everything works as it should. In the datasheet, they write only the maximum recommended values, I see no reason for different values on the plus and minus regulators. That's why I ask.
Strange as the datasheets clearly show different values for same voltage output for the two regs. Now this is also a difference ratio between the resistors ? And the programmable Lt19xx and LT30xx are also different than the standalone voltage output ones ?
No, the resistor ratio must be the same. It can be seen from the formula of the output voltage. The only difference is that the current on the Adj pin is lower with the LT3015 than with the LT1963, but if the resistor values are small this is negligible. And you have a trimmer for fine tuning.
I used fixed resistors that I had. I achieved +-4.98V, +11.44V and -11.51V. I can adjust more accurately, but I don't care if it's 12V or 11.44V/11.51V on the Sparkos.
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I doubt there is any difference in performance, just that they are fixed output voltage. And therefore simpler to use.
Yes you can use the same "ratio" values for both sides. I only followed datasheet for the quiescent current, but it seems be not very important for the performance of these regulators 😉
Thanks Miro, that's what I thought. So all values of resistors, trimmers and capacitors could be as for LT1963. I do not recommend the other way around.
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Very nice project. Was looking for something like this. Looks perfect. But the gerbers on #1 are they the latest? There seems to be more versions during this topic. Idem question for the PSU1.
Probably because they are really different. 🤣
Datasheet is datasheet, you didn't make these DACs exactly according to the datasheet, but it still turned out well beyond all expectations.
In principle, in those places, smaller resistors are always placed on that voltage divider than is prescribed as max. value in the datasheet. Some put larger resistors abusing the safety margin left by the manufacturer for the voltage regulator to work properly.
I'm not al that at home at the data transfer. But can i use my Ian Canada Fifipi fot the I2s or is there some extra board/converting required?
@Arnolddew What is your source device for audio transfer? Is that USB, optical, bluetooth, lan or sd-card?
RPI is connected through LAN or USB? .... Best if you buy some USB-I2S device and connect it directly to USB in your Mac Mini. You can also connect this USB-I2S directly over raspberry usb #1373 😉
You can start with the cheapest USB-I2S device ... the sound will be very good: https://www.aliexpress.com/item/4000166755098.html
You can start with the cheapest USB-I2S device ... the sound will be very good: https://www.aliexpress.com/item/4000166755098.html
PCM63P DAC plays even better now. The bass is even stronger now than it was then. The middle tones are even more natural and lively. This DAC must be allowed to play for at least a month. Nothing should be touched for at least a month. Then it shows the maximum.👍
So like wine, maybe in 10 years it will be even better, and maybe during that time you will learn to make a good tube output.🤣🤣
I hope that after this I will be in the ignore list because it is a sin to mention the tube here.🤣🤣
I hope that after this I will be in the ignore list because it is a sin to mention the tube here.🤣🤣
No No Grunf, don’t stop tube talk!! I’m currently working on a 6n6p output stage and experimenting with an SMPS for HV/Filament power.
There is more than one way to skin a cat as they say, tubes are just another flavor 🙂
There is more than one way to skin a cat as they say, tubes are just another flavor 🙂