I found this decoder by Pavouk, from long ago. Seems like is still being used in recent equipment. The thing that bothers me is that 7-12V AC is being used with a bridge rectifier instead of using just 7-12VDC. Is there an obvious reason for doing so?
BTW is this really still being used? I mean even AMB gamma 1 and Twisted Pear S/PDIF Transceiver uses similar chips.
BTW is this really still being used? I mean even AMB gamma 1 and Twisted Pear S/PDIF Transceiver uses similar chips.
Unless you are using battery, you've got to get from AC to DC, whether it's on the same PCB as the chip or somewhere else.
What are you trying to do?
What are you trying to do?
Thats a fair point, I guess I should have been clearer. What I'm trying, is building a DAC inside a preamp (Nutube B1), I want to input from TOSLINK and be able to play it in the B1.
I'm already converting 220vac to 12vdc inside the case (separate for B1 and for an input selector) so I have already a 12vdc which I can use instead of stepping down 220vac to 12vac. I just found it weird to go from 12vac to 12vdc istead of 220vac to 12vdc.
That schematic actually IS saying to go from 220/120 down to 12v AC.
What you see there is the secondary voltage of a power transformer. He just didn't include the primary voltage and the transformer symbol because it is implied that you know there is supposed to be a power transformer there.
If you already have a free 12v dc line, feel free to use it and run it through the regulation stage as shown in the diagram.
But that is exactly what the schematic does. 220vac to 7 - 12vac winding off transformer to bridge. Some of my old dev boards do the same thing. They take AC or DC.
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If the 12v you have is AC voltage from a 12v tap on a transformer, then it needs to be rectified.
If for what ever reason the 12v ac has already been rectified to DC, then you are good to go.
Arguing about your power supply irrelavent until you have your whole design worked out. What about the DAC itself? The circuit you linked just gets you from S/PDIF to I2S. What does EVERYTHING inside your finished chassis look like?
Not irrelevant if you have the other parts already designed. Im using a Gamma 2 as DAC. I'm not 100% done with all this digital to analog thing, I'm figuring out how to connect everything and if using this DIR90001 a gamma 1 or a Twisted Pear wm8804, but looking for my best options and possible connection between equipments, that's why I asked about the power supply. I'm already supplying 12vdc to an arduino for my LCD screen so I wanted to use that same power output.
You definitely are testing my patience, that's for sure. You are asking questions but only providing the needed info in dribs and drabs. What EXACTLY are you building? Are you using commercial PCB's, PCB's of others, your own PCB's, perf board? These are the kinds of details needed. The chips themselves are all 5VDC and/or 3.3VDC so the supply is a small issue when you know the details.