NAS/MEDIA PLAYER線性電源pcb

johnme

早排試左lt1084同sigma11比電nas再出dac,
聲音不錯,
手痕做左個lt1084 pcb layout,
睇睇各位有咩comments,
再攞去做pcb.

johnme

手痕做多個sigma11 modified版,
用tmc compensation,
但係可以還原做原本sigma11,
只要唔用r4,
c9, c10 用3900p接上,
再接c11 220p

tmc版(未經測試)就唔用c11,
c9, c10用220p,
r4用1k.

edison133

Ching, why not use current diode?

johnme

edison133 發表於 2014-4-3 22:09
Ching, why not use current diode?

the fet is more easy to find than current diode and cheaper
but, you have to test the Idss by yourself.

billymud

how many boards u plan to fab?  
make it a GroupOn for 76fellows ??


incorporate protections and supressions ?
enlarge ground plate ?
R2 be multi-turn VR for LT1084_adj ?
add output terminals for flexibility ?
relocate voltage sensing point ?

johnme

billymud 發表於 2014-4-4 03:04
how many boards u plan to fab?  
make it a GroupOn for 76fellows ??

本帖最後由 billymud 於 2014-4-4 04:06 編輯

how many boards u plan to fab?  
make it a GroupOn for 76fellows ??

reg bd1.jpg
incorporate protections and supressions ?
enlarge ground plate ?
R2 be multi-turn VR for LT1084_adj ?
add output terminals for flexibility ?
relocate voltage sensing point ?

1. about 10 pcs only, more than enough la,
no group buy at the moment as I will use these board
for testing different caps and set up for best sound possible.
But ,I won't mind giving out some test boards to other members at cost level.

2. The LT1083/4/5 family can stand for 50A backward current, so no protection diodes need, for 104 suppresion, I though that 1u is good enough but I won't mind adding a place for additional 104 caps.

3. frankly speaking, I do not really understand how to use ground plane effectively. Can you tell us more about it?

4. It is a matter of flexibility vs simplicity. I once have a faulty VR, so I prefer simple resistor.

5. Good idea

6.Great, you have good eyes. I will re-do the layout a bit.

Thank you so much.

johnme

講多少少.

小弟已經做左一個搭棚LT1084,
同一個SIGMA11比NAS.

比較過兩者,
其實都比跟機好上不少.
有C-HING試用過唔同電容落LT1084效果差很遠,
他SUGGEST C7~C9用0.33U PANASONIC POLYESTER, 兩粒220U PANASONIC FM,
由於小弟冇PANASONIC POLYESTER,所以用上PANASONIC POLYPROPYLENE 0.47U,
同時小弟FUT然色盲,
插左FC而唔係FM,
不過OUT位插第2粒220U時,
SQ改善明顯,
值得一試.

另外,CADJ個粒CAP,
原廠SUGGEST 10U,
用0.47U的話,
可能太少,
所以多留一個位C6插CAP,
各位(小弟)可以試由10U試到100U,
應該會搵到個SWEET SPOT,
但係腳位用5MM好似大左D.

billymud

johnme 發表於 2014-4-4 08:45
講多少少.

小弟已經做左一個搭棚LT1084,

I can free u a few pcs of PANASONIC POLYESTER caps for experiment, after returning to HK la~~

"....多留一個位C6插CAP,各位(小弟)可以試由10U試到100U,..." that explains why u need to incorporate the Dy for protecting the LT10xx from damage due to the "unexpected" discharging energy of 100uf.

as remote sensing will be applied in next layout, a quality multi-turn VR (e.g. Burns) would be necessary.   

ground plate example

johnme

billymud 發表於 2014-4-4 15:18
I can free u a few pcs of PANASONIC POLYESTER caps for experiment, after returning to HK la~~ {:1_ ...

Sounds great, I will ask you for the polyester caps later.

Here is a modified version.

I put the ground plane on top. (lazy to change layers).

OR, in a single side ;p

as remote sensing will be applied in next layout, a quality multi-turn VR (e.g. Burns) would be necessary.

what do you mean?

billymud

remote sensing for a better job.