DAC AD1862: Almost THT, I2S input, NOS, R-2R

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PSU 1 not only for AD1862

PSU 1
is a simple DIY power supply based on MC78xx/MC79xx regulators. These regulators are underestimated by many people due to the higher noise specs compared to other „more advanced“ regulators. This regulator is very stable even for a pulse load. For audio applications it is sufficient form my experience ... and is very cheap :D

In the basic configuration, components are set to output +/-5VD and +/-12VA for AD1862 DAC.
Since PCB is universal, you can solder components for any other DAC voltages.
The PSU needs 2 separate transformer windings. Voltage is rectified through schottky diodes bridge and goes to a big CRC bank, which makes the voltage smoother for regulators. CRC combination works as a filter with frequency cut of 23 Hz. It should help to the purity.
An external regulator can be sourced from the CRC (PCB contacts V+, GND, V-).
Output from the regulator includes another big low ESR capacitor for the final filtration. The 78/79 regulator has an emitter folower stage with no gain, so the big output capacitance makes no difference to the phase shift, thus stays stable :scratch2:
The output power and heatsink is a DIY question, but since the AD1862 DAC consumption is small, it should go without heatsink.

PCB size is 75x150mm and can be cheaply ordered from jlcpcb or any other PCB manufacturer (gerbers included in the post).
(it was not tested at the time of writing this post)

Example list of components (copied from BOM picture, except resistors)
mouser:
603-FMP300FRF73-1R
R79IC3100Z340J, 505-MKP2D031001FJO00
505-MKP20.33/100/5
647-UHE1E472MHD
647-LKG1V682MESYAK
604-L483GDT
511-1N5822
863-1N4007G
863-MC7805ACTG
863-MC7812ACTG
863-MC7905ACTG
863-MC7912ACTG
534-4628
576-0216001.MXR20SPP
651-1729128
651-1729131
ebay: 233823483402, 233670142926
I’m trying to figure out a current parts list (bom) for the psu 1 and some of the regulators are no longer available through Mouser What are suitable replacements?
Thank you
 
Hi there.I am just started soldering on PCB.
There are +- on PCB (C15,C25)that suggests electronic cap. Are there any problem if I solder PML cap at there?
 

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Interesting reading on the PSUs there. I have built a PSU 1 hot rod using Aliexpress regulators that use the Ti TPS7A chips. Have had good results with them in my Cambridge Audio Dacmagic.
I was thinking just recently if the 4700uf on the outlets would suit them . Have read the datasheets.
I guess I will try the PSU with them and maybe with some lower values too.
Hello Jim,
Curious if you’ve experienced any issues with the TPS7A regulators with your hotrod PSU1? I’m slowly compiling a bom and am building up 2 psu1 boards. Parts are not that expensive so why not. But I would like to at least configure them somewhat differently and I noticed your use of the TPS chips and as I read through I see some questions regarding stability and the output capacitor sizes? Again, just curious if you have some insight.
Anyway, hope you’re doing well
Ps. I would also like to build up a psu 2 but am unsure where to get the pcb.
 
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Hello again jazz. Hope your build is going well. On my hot rod psu1 I only have 47uf on the outputs after the Ti regs. All seems very well. Sounds brilliant and runs cool so I assume no instability.
Please try a JLCPCB order for your own PSU2 pcbs. You will never look back!
 
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Hello again jazz. Hope your build is going well. On my hot rod psu1 I only have 47uf on the outputs after the Ti regs. All seems very well. Sounds brilliant and runs cool so I assume no instability.
Please try a JLCPCB order for your own PSU2 pcbs. You will never look back!
Hey Jim,
The jlcpcb site looks interesting. My plan is changing. I’m looking at doing a psu1 stock and one of yours with TI regs. Also considering doing a psu 2. But I’m not sure what differences to expect with each. Thanks for your help though
 
Im running a JL Sounds USB to I2S III board on the "not flipped" 1.3 Miro board

Using the JL Sounds USB drivers 4.82.0, everything was sped up from any source

Uninstalled the JL drivers and allowed Windows to find it on it's own - speed is back to normal

Weird. Going to have to play with this more tomorrow

Yes J4 is closed