TDA1541A non-o/s DAC PCB

[Pedja]

The reason I gave importance to this is that I think this could really make problems. You will easily find 15mm MKP but you will not that easily find ones 5mm or less wide.

I have not settled on what I settled in a minute or two. If memory serves me well, when I was playing with this I have that issue, if I wanted to keep decently sized tracks between the TDA and these caps, yet 6mm wide caps meant they will be at least a few mm farther from TDA – they have been spreading more left and right looking from TDA’s pins and the routing of these tracks became more problematic.

Maybe the alternative could be some smaller (lower voltage) axial pieces.

But don’t forget that as long as you do not decide to use one cap up - on cap down strategy, you need caps wide 5mm or less.

Pedja

[JonPike]

Originally posted by Pedja

What is interesting about MKP10 0.1u/160V is the fact Buerklin gives the same dimension for these like for 0.1u/250V while WIMA datasheet claims something else.
http://www.buerklin.com/gruppene/KapD/D103240.asp?l=e
http://www.wima.com/wimaforhcr.pdf

Mouser confirms WIMA’s data:
http://www.mouser.com/catalog/617/451.pdf

What are the real dimensions? Or are there two same capacitance/voltage pieces of the different dimension? It is specified sometimes in WIMA’s datasheets, not in this case though.

I guess it is not a problem to use values somewhat higher than 0.1u at all the pins but I do not know if thus something will be gained or not.

Pedja

Having an actual Wima .1uF 160V cap in my hand, and my set of calipers to measure.. this is what I get:

Width: 4.95mm
Length: 17.98mm (of body)
Height: 10.96mm
Lead spacing: aprox 15mm (15.85mm outer edge of leads)
Lead diameter: .81mm

Hmmm... just went to Mouser to see what they say, and it DOSEN'T match.. went to Wima and it's the same.. The interesting thing is that the package size is the same as what they have for 250v models, 5x11x18 and 15 spacing, as opposed to the 160v that should be 6x12.5x13 and 10mm spacing.

Yet, it's marked as a 160v part. Wonder if they decided to quit the other size, and just market 250's as 160? Are my parts old (have no idea how long they've been in that drawer at my work) and there is a new size now? A mystery... and I was hoping to clear things up..

The voltage rating of course isn't an issue, but will the wider (6mm vs 5mm) parts have spacing problems on the board? If not.. no problems.

On the other value question.. I have seen some builders of this chip state that .22uF possibly sounds better... and one guy saying that .33uF was getting worse again, but I have no direct idea how true this may or may not be. TDA1541A parts datasheet shows .1uF at that location.

There is a Wima .22 160v that is 7x14x18 and 15mm spacing, if it isn't too wide, but Mouser dosen't stock them.. have to go to Wima or a distributor.

[Rotellian]

I feel i must agree with Jean-Paul - if something is to be done do it on the next revision. Pedja has done a lot of work so far (and very impressive it looks too!) and i feel its too much to ask him to alter it. Im quite sure we can all find/buy suitable caps to fit.

[Pedja]

Originally posted by JonPike
Having an actual Wima .1uF 160V cap in my hand, and my set of calipers to measure.. this is what I get:
Width: 4.95mm
Length: 17.98mm (of body)
Height: 10.96mm
Lead spacing: aprox 15mm (15.85mm outer edge of leads)
Lead diameter: .81mm
Hmmm... just went to Mouser to see what they say, and it DOSEN'T match.. went to Wima and it's the same.. (…)

I checked something about the dimensions of WIMA’s and there is a bit of confusion here. They definitely have some values that are (or were) manufactured in a few packages (3 in some cases) and not all packages are listed in their datasheet and 0.1u/160V MKP10 is obviously among them. Maybe (just a guess) Mouser sells 15mm leads spacing units, maybe they just rewrote the data from the datasheet?

Once again: 6mm wide parts won’t fit for C105-C110 and C113-C118, 5mm is maximum here. C111 and C112 could be 6mm wide. The units I use here are Bürklin parts # 43 D 222.

Bzo, from the Digi-Key’s catalog pages you have linked it seems like BC Components MMKP383 0.1u/250V (Digi-Key # BC1812-ND) will fit very well. Possible alternatives are BC MKP417 0.27u/160V (DK # BC2118-ND) and BC MKP418 0.15u/250V (DK # BC2160-ND). As I can see all are on stock. I couldn’t see anything from Panasonic that will fit though.

Pedja

[JonPike]

OK.. If it's 5mm max, it's 5mm max..

So someone needs to talk to Mouser, and find out if they have the 5mm wide 15mm lead spaced parts or not.. as well as talk to a Wima rep in regards to where to find the .1uf 250v parts that are "officially" that size... I've gotten too busy at work the past few days to squeeze that in, or I'd do it tomorrow..

[bzo]

Pedja, is C19' on the back side of the board? If so, what is the footprint of that component? I think I'm going to start ordering some components soon.

thanks for looking at those BC Components parts btw.

[Pedja]

Yes and it goes directly between the pins 5 and 15, so there are no pads for it. Some axial part about 20mm long might be here more convenient than radial one.

[jean-paul]

FYI, the Wima MKP10 0.1 uF 160V I have are 15 mm from pin to pin.

[bzo]

For those of you in North America, I just got a quote back from Victoria Magnetics on the following transformers, including mounting hardware. I'm not sure why I didn't spec the extra 5V line for the reclocker at 2A, but it probably has a negligable effect on the price to do so.

Transformer 1 - $94
2 8V @ 1A
3 8V @ 1.5A
1 22V @ 2A
2 17V @ 1.5A

Transformer 2 - $91
2 8V @ 1A
3 8V @ 1.5A
1 22V @ 2A

[siu sin man tho]

HI BZO,

when I design my PCB & test the power transformer for the tube I/V stage & Digital stage.
I test several different power transformers.
All were high quality.
I test in same watt of EI, c-core, circle core & R-core.
At last I choose of R-core because compare the sound quality.
The R-core was the sec. best. C-core is the best but expensive.
EI had the best punch/bass quality of all transformers.
the photos show was the r-core I choose for my parallel TDA1541A PCB use. Every kit will use two R-core power transformers.

I prepare to sell to all diyers for USD 100 per pair include postage post worldwide.

Every power transformer is 25 watt power.

thanks

thomas

www.diyaudiocraft.com