billymud 發表於 2014-4-13 02:27 static/image/common/back.gif
your final build may be look like this !
冇人地o甘靚仔{:1_351:}
2Oz銅都幾"罪"手o下{:1_338:}
放假有野玩{:1_340:}
本帖最後由 billymud 於 2014-4-16 01:42 編輯
good jobs !{:1_352:}
u should hv the polarities of LED and DC_ouputs marked on pcb.{:1_343:}
hv u the right heatsink fabricated ? {:1_339:}
billymud 發表於 2014-4-16 01:30 static/image/common/back.gif
good jobs !
u should hv the polarities of LED and DC_ouputs marked on pcb.
I think that some of the remarks were not printed.{:1_352:}
In Post #2, you can see some words were written on the board
but they do not appear in the final board.
Let me check the gerber files and see what happens.
About the Led, maybe the silkscreen is overlapped with the footprint.
The polarity is not shown clearly.
The same thing did happen in the last Cmoy PCB.
I have test a heatsink 10 x 7.5 x 3.5 cm with the LT1084.
After playing music for hours, it only gets warm (about 30C or less).
If I can get a heat sink with width 7 cm or 6.5 cm.
It will fit perfectly with a commonly available case.
I will post a photo of the case tonite.
I will test the heatsink with the Sigma and see if this size works well with it.
Billy, I need your advise about decoupling and bypassing the regulators.{:1_351:}
I will post the questions after I take more photos about the regulators tonite.
good job!
johnme 發表於 2014-4-16 08:05 static/image/common/back.gif
I think that some of the remarks were not printed.
In Post #2, you can see some words we ...
u can always homebrew a heatsink in smaller size with copper, instead of aluminum, with equivalent performance or even better.
本帖最後由 billymud 於 2014-4-17 01:52 編輯
johnme 發表於 2014-4-16 08:05 static/image/common/back.gif
I think that some of the remarks were not printed.
In Post #2, you can see some words we ...
homebrew a heatsink in smaller size with copper.
also, applicable for Shunt Req.......... {:1_263:}
d板巧靚^^
本帖最後由 billymud 於 2014-4-18 10:46 編輯
this photo exhibits a comprehensive decoupling and bypassing scheme of LPSU.
u may like to put the caps on side-2 (bottom side) of the pcb, alteratively....{:1_263:}
本帖最後由 johnme 於 2014-4-22 17:40 編輯
用pcb完成第一個lt1084-adj regulator啦,
一開聲已經不錯.
Cadj最後決定試用100u//0.47u,
(加粒100u個noise floor低20dB)
水塘比原本用洞洞板細,
用兩粒PANASONIC 4700U//1U polyporpylene,
decoupling cap用220u,
全部cap都係panasonic.
rectifiers用mur820.
film cap要用鉗反直先插落pcb,
可以令cap腳短d,
反應好d.
幫同事做多兩個,
比NAS同MEDIA PLAYER~{:1_263:}
因為冇晒LT1084,
改用LM1084,
為方便比較,
其中一塊有用billymud兄suggest既,
兩粒0.1u bypass HF noise.
