Hello Doede,
I am presently building a V3 version and wonder what voltage value transformer to buy for the PSU. In any case it will be minimum 50VA as I already heard the effect of more power in the transformer on my current 8 decks DDDAC (V1 V2 mix).
As I had to tweak, with you help, the old PSU when I went to 8 boards, Today I prefer asking before buying my transformer. (Toroidy supreme audio grade in mind)
From PSU Building instructions:
Optional chokes
Suggestions are between 50mH and 1H – as long as the DC resistance is below 4 Ohm. This applies, when used with the DDDAC1794MK3 board (1 or 2 boards)
Maximum current output
The PSU can deliver easily 1A or more. But with the delivered heatsinks it is intended for maximum two DDDAC1794MK3 DAC boards, where redominantly the analog section (9 Vdc) is drawing up to 200mA per Board. Two boards are below 400mA and perfectly safe when a 12 Vac transformer is being used. For higher currents increase of heatsink size is necessary! This is DIY experiments…
My understanding:
A 4 Ohms choke will add 1.5 Volts ( 0,22 resistor out ≈ +0,1V) drop for 2 boards and 3,1V drop for the silly boys like me who may use 4 boards.
In the chapter about old PSU tweaking you stated a 5,5V headroom is needed.
Guessing it is still same requirement, needed headroom is 8,6V with four boards if I am correct.
My question is:
Will a "powerful" 2X12V transformer still do for the task when switching to 4 boards or do I need a bit more voltage?
Thank you for advising.
PS: The kits are a pleasure to build with amazing board quality. Thanks!
I am presently building a V3 version and wonder what voltage value transformer to buy for the PSU. In any case it will be minimum 50VA as I already heard the effect of more power in the transformer on my current 8 decks DDDAC (V1 V2 mix).
As I had to tweak, with you help, the old PSU when I went to 8 boards, Today I prefer asking before buying my transformer. (Toroidy supreme audio grade in mind)
From PSU Building instructions:
Optional chokes
Suggestions are between 50mH and 1H – as long as the DC resistance is below 4 Ohm. This applies, when used with the DDDAC1794MK3 board (1 or 2 boards)
Maximum current output
The PSU can deliver easily 1A or more. But with the delivered heatsinks it is intended for maximum two DDDAC1794MK3 DAC boards, where redominantly the analog section (9 Vdc) is drawing up to 200mA per Board. Two boards are below 400mA and perfectly safe when a 12 Vac transformer is being used. For higher currents increase of heatsink size is necessary! This is DIY experiments…
My understanding:
A 4 Ohms choke will add 1.5 Volts ( 0,22 resistor out ≈ +0,1V) drop for 2 boards and 3,1V drop for the silly boys like me who may use 4 boards.
In the chapter about old PSU tweaking you stated a 5,5V headroom is needed.
Guessing it is still same requirement, needed headroom is 8,6V with four boards if I am correct.
My question is:
Will a "powerful" 2X12V transformer still do for the task when switching to 4 boards or do I need a bit more voltage?
Thank you for advising.
PS: The kits are a pleasure to build with amazing board quality. Thanks!