Hi. I´m a newbie to digital, and I´m making a dac around CS8414/pcm1730 chips.
For each chip, I have made some kind of smd¨adaptor¨, etching little pcbs (app. 2x2 cms.).
Those pcb´s will be soldered ¨smd style¨ to a continuous, solid ground plane. Trying to make sense of the things that I have read in other threads about digital grounding ( yes, I have searched...), the ground plane will be ¨intact¨, without vias and without any kind of interruption.
The separation between chips and ground plane will be +/- 0.6 mm.
Chips will be connected with ribbon cable, flat against the ground plane, and oriented in such a way that there will be no crossing of signal carriers and power supply conductors.
Now, the tricky part:
Which of the following options -if any- is the better way to provide power and grounding to the final pcb?
1) With twisted pairs (v+ and gnd), right to the main IC´s pins, from an independent, grounded modular pcb with rectification, regs etc contained in that board?
2) Ditto, but placing the regs in the dac board, as close as possible to the main chips?
3)Or sending the various v+ needed (+5v analog, +5v digital, + 3.3v digital and +/- 12 v analog for the output stage) with separate single cables, and only one ground cable connected to a star point in the psu board? (sounds weird...)
3)Is any other kind of ground connection needed for the main pcb? (I ask this because, in some pcb´s, I have seen additional grounding to chassis provided with screws attached to the pcb ground and uninsulated standoffs)... And for the SPDIF input?
I´ll appreciate any input on this confuse ítem. I´m trying to maintain loops as small as possible, a difficult task with single sided pcb´s .
Thank you very much in advance.
For each chip, I have made some kind of smd¨adaptor¨, etching little pcbs (app. 2x2 cms.).
Those pcb´s will be soldered ¨smd style¨ to a continuous, solid ground plane. Trying to make sense of the things that I have read in other threads about digital grounding ( yes, I have searched...), the ground plane will be ¨intact¨, without vias and without any kind of interruption.
The separation between chips and ground plane will be +/- 0.6 mm.
Chips will be connected with ribbon cable, flat against the ground plane, and oriented in such a way that there will be no crossing of signal carriers and power supply conductors.
Now, the tricky part:
Which of the following options -if any- is the better way to provide power and grounding to the final pcb?
1) With twisted pairs (v+ and gnd), right to the main IC´s pins, from an independent, grounded modular pcb with rectification, regs etc contained in that board?
2) Ditto, but placing the regs in the dac board, as close as possible to the main chips?
3)Or sending the various v+ needed (+5v analog, +5v digital, + 3.3v digital and +/- 12 v analog for the output stage) with separate single cables, and only one ground cable connected to a star point in the psu board? (sounds weird...)
3)Is any other kind of ground connection needed for the main pcb? (I ask this because, in some pcb´s, I have seen additional grounding to chassis provided with screws attached to the pcb ground and uninsulated standoffs)... And for the SPDIF input?
I´ll appreciate any input on this confuse ítem. I´m trying to maintain loops as small as possible, a difficult task with single sided pcb´s .
Thank you very much in advance.