We are looking at using the Traco THN 15-1225 to provide +/-24v rails from any typical DC input. It's pricey at $41 but avoids mains. We then follow with Texas Instr. TPS7A4701RGWT for a 4uV noise LDO regulator on positive rail, and TPS7A3301RGWT LDO for negative rail. Also will use a Wurth Electric common mode choke to clean it all up. About $60 total in parts for PSU but it is a state of the art integrated solution that is very clean and safe.
THN 15-1225 TRACO Power | Mouser
TPS7A4701RGWT Texas Instruments | Mouser
TPS7A3301RGWT Texas Instruments | Mouser
74482210002 Wurth Electronics | Mouser
Let us know what you guys think - is the integrated PSU too expensive and you would all rather make your own trafo/CRC/VR's?
JPS64 was playing around with metal core PCBs that bolt onto some Fischer heatsinks - but just as easy to bolt them to the bottom or side walls of an aluminum enclosure. You can see how small the PSU DC-DC converter and LDO's are.
THN 15-1225 TRACO Power | Mouser
TPS7A4701RGWT Texas Instruments | Mouser
TPS7A3301RGWT Texas Instruments | Mouser
74482210002 Wurth Electronics | Mouser
Let us know what you guys think - is the integrated PSU too expensive and you would all rather make your own trafo/CRC/VR's?
JPS64 was playing around with metal core PCBs that bolt onto some Fischer heatsinks - but just as easy to bolt them to the bottom or side walls of an aluminum enclosure. You can see how small the PSU DC-DC converter and LDO's are.
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Hmm sounds good - I'm probably still in for the board but due to the psu components cost might not be something I build right away though...or may just use a lab supply in the meantime 😀
Not sure what the final design of the pcb would be like but maybe you could make it one pcb with the option to snap off the psu section for people who don't want it? Just a thought
Not sure what the final design of the pcb would be like but maybe you could make it one pcb with the option to snap off the psu section for people who don't want it? Just a thought
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Looks a nice cute design, DC PSU module is good, I have a 30VDC printer supply here that would be perfect.
Please put me down for one stereo set of boards.
Please put me down for one stereo set of boards.
Looks nice!
It would be cool to add in a xfeed circuit that can be switched on and off option while your designing the PCB?
Do
It would be cool to add in a xfeed circuit that can be switched on and off option while your designing the PCB?
Do
how about power supply given in http://www.linearsystems.com/lsdata/others/Headphone_Amplifier_Evaluation_Board.pdf
So here is some more progress... We are thinking of also adding a cap multiplier to give a graceful slow ramp turn on to prevent headphone thump and also to prevent the DC-DC from auto-shutdown due to cap in-rush current.
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GB interest list:
By pair, it is meant a stereo integrated board. If you want qnty 2 of a stereo board, please indicated such.
I am assuming folks who responded with questions above are "interested" if not, please remove your name and sorry for assuming too much.
By pair, it is meant a stereo integrated board. If you want qnty 2 of a stereo board, please indicated such.
I am assuming folks who responded with questions above are "interested" if not, please remove your name and sorry for assuming too much.
GB interest list:
Badboygolf16v - 1 pair
Dabore84 - 1 pair
funch - 1 pair
kartk - 1 pair
Yourownbuzz - 1 pair
BabyDontHertzMe - 1 pair
Stellarelephant - 1 pair
passive420 - 1 pair
Pinnocchio - 1 pair
vvs7 - 1 pair
sarathssca - 1 pair
Gwrskien - 1 pair
By pair, it is meant a stereo integrated board. If you want qnty 2 of a stereo board, please indicated such.
Badboygolf16v - 1 pair
Dabore84 - 1 pair
funch - 1 pair
kartk - 1 pair
Yourownbuzz - 1 pair
BabyDontHertzMe - 1 pair
Stellarelephant - 1 pair
passive420 - 1 pair
Pinnocchio - 1 pair
vvs7 - 1 pair
sarathssca - 1 pair
Gwrskien - 1 pair
By pair, it is meant a stereo integrated board. If you want qnty 2 of a stereo board, please indicated such.
Ok this is starting to look much better in terms of interest. The design is still evolving and I just ordered the PSU components to test in a hand etched proto type to ensure the PSU meets the performance goals and works well and reliably.
If the PSU works, it might be a nice building block for a lot of different amplifiers. It gets away from all this linear transformer and shunt regulators etc that are trying to knock down 50Hz/60Hz in the audible band by -100dB or more. With switching supplies and cap multipliers, I have been able to get it to go down to the noise floor of the amp like a battery.
If the PSU works, it might be a nice building block for a lot of different amplifiers. It gets away from all this linear transformer and shunt regulators etc that are trying to knock down 50Hz/60Hz in the audible band by -100dB or more. With switching supplies and cap multipliers, I have been able to get it to go down to the noise floor of the amp like a battery.
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Is the power supply given above reference doesn't meets the current requirement ? Is the filtering given there be ok or does it needs further filtering for low power requirements?
So I looked at the PSU in the above article (shown here for convenience). I’m sure it works well too but really is not quite the same level of modern SOA implementation as my design which also uses a dual rail DC-DC step up (Traco THN15-1224) plus a TI LDO regulator with 4uV noise, plus a cap multiplier and a CRCRC filter. Basically everything thrown in for good measure. Although I will test first and se if a cap Mx is needed. The LS HPA PSU appears to use a MOSFET capacitance multiplier as well. I don’t know what current rating it is for but the one JPS64 and I are designing has max +/-315mA current and +/-24v which we can adjust from 23v down to whatever we need with programmable low dropout (LDO) voltage regulator TP7SA. Nominally 15v or 18v at 115mA to up to 300mA (for those with big heatsinks). Can accept 9v to 18v dc input and has 90% efficiency.
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Ok sounds like this thing is happening - in that case I'll wait for this PCB and get the AKSA preamp PCBs posted together if thats ok with you X?
Thanks for the link. I get a lot of boards from JLCPCB. Had no idea how many steps are involved and how spread out the factory is. That’s $B worth of equipment to do what they do for $2 for 10 boards (2 layer 10cm). My boards nowadays cost a lot more since thick 2mm, double thick gold, ENIG finish. The integrated amp with PSU will be premium construction like this.
More progress from JPS64. This is going to be one heck of feature rich amp. Notice the symmetry of the amp core. That’s how JPS64 says to keep noise down, one must “Think like an electron”, sung to the tune “Walk Like an Egyptian”.
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Would it be possible to have holes on the pcb for the switchcraft 3.5mm sockets as input and output?