GB: A Simple Discrete Current-Mirror IV Converter, à la AD844

[Myint67]

GB2/Waiting List

Kokanee - 2 PCB + 12 transistors
baswamin - 2 PCB + 12 transistors
asanden - 2 PCB + 12 transistors
simon dart - 4 PCB + 24 transistors
BRN - 2 PCB + 12 transistors
Myint -2 pcb + 12 transistors
Others who are interested, please update the above list.

Thanks

 

[rss388]

Have been out of town for a while. Just came back and found in the mail an envelope from Ripster.

I take my hat off to you Ripster -- a lot of hard work and so neatly packaging all the sorted parts and then sending off to so many people!! Thanks again!!

 

[Johnny Canuck]

GB2/Waiting List

Kokanee - 2 PCB + 12 transistors
baswamin - 2 PCB + 12 transistors
asanden - 2 PCB + 12 transistors
simon dart - 4 PCB + 24 transistors
BRN - 2 PCB + 12 transistors
Myint -2 pcb + 12 transistors
Johnny Canuck - 1 pcb + 6 transistors

Others who are interested, please update the above list.

 

[jimk04]

A quick question if I may. Studying the boards in my hands against the images on the pdf and repeated in this thread. I noticed my boards are a mirror of the photos. Then I see on thr images v1.0R. I have v1.0L (×5). Should we have L and R boards?
Thanks

Edit.....dang.....post 1 states L and R boards.

 

[EUVL]

Post #1 :

1 set includes 5 PCBs, left / right versions, of which 2 pairs will be supplied.
There is an additional "neutral" version which is meant for test build.

So 2x L, 2x R, 1x "neutral".


Patrick

 

[jimk04]

Yes sorry Patrick I edited my post. I have 5 x Left.

 

[Ripster]

Wow, I thought the PCBs were all the same. I was not aware there were different PCBs. I just thought that you get 5 PCB 2 for left 2 for right and one for test! I did only a quick inspection after receiving them (they all came in one bundle not separated) and they all look the same to me, not being aware that there are different versions.

So what is the difference between boards except being inverted?

 

[jimk04]

Just a mirror image layout wise. I guess just to neaten wire runs in and out.

 

[jimk04]

I have contacted the 2 other UK buyers to see if they have any R boards.
Hopefully we can sort this with some cooperation. Maybe a US, EU members could help also.

 

[EUVL]

The boards are identical in circuitry terms.
So you do NOT have to have R&L versions.
They are only more important when you build them as a pack in balanced mode.
A Simple Discrete Current-Mirror IV Converter, à la AD844

I would not worry too much about it.


Patrick

 

[Ripster]

Guys I am really sorry for this mistake. After all this work I am really disappointed I wasn't paying more attention to PCBs. If anyone will have any troubles just contact me and we will try to resolve this in any way possible.

 

[jimk04]

I don't think it is an issue ....like Patrick says. Holding my 2 left boards over my Miro AD1862 and it will all work and lay out perfectly fine. Sorry for raising a false alarm. It was just the mirror image photo that caught my attention.
As you were gentlemen!

 

[EUVL]

> Guys I am really sorry for this mistake.

No real harm done, only cosmetic issue.
The matching is a MUCH more important contribution to best results.


Cheers,
Patrick

 

[jimk04]

Indeed. We will be fine with the boards we have after the mammoth task you undertook

 

[Jcris]

Is the group buy still going on?

 

[jimk04]

John...I believe not but there appears to be a 2nd list forming a few posts back. Whether Ripster will go thru with this I cant say.

I don't know if this is the place to talk about building tjses things but here I go anyway...please advise if there is a better thread.


I am creating 4 rails, so 2 pos and 2 neg but using 4 times LT3042, so obviously each will have its own winding and rectifier.
Regarding transformers that I wish to order, I though about using small 'blue' encapsulated trafos. Maybe 6va so 3va per regulator. Is that enough or should I be upping the power rating.?
Regards
Jim

Edit....sorry I forgot about the 'other ' thread discussing this design. Shall ask there

 

[EUVL]

Someone asked about a component pad in series with the input.
This is for a 0603 0R (jumper) resistor if you are using 1mA DAC current.
If you have more DAC current, you need to use multiple modules in parallel.
In that case, you should use a 1R resistor at that location.

So at least one person has started building.


Patrick

 

[Vunce]

Yup, that was me, guilty as charged. Thanks for the clarification of this resistor/jumper pad Patrick
I finally got a chance to solder up a pair of boards, neat little buggers! Next step will be fine tuning with the trim resistors.

 

[EUVL]

Very nice SMD soldering.

To top it all, use some #400 wet and dry sand paper to clean off the pcb rough edges.
Actually best before soldering, but still possible after.


Patrick

 

[Vunce]

Good tip
I use a fine set of files to clean up the pcb edges.