Jump to content

goldenreference low voltage power supply


Recommended Posts

  • Replies 654
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Popular Posts

So I think this is pretty cool (sorry to toot my own horn, but I can't help it sometimes ).  I've been meaning to miniaturize the GRLV supplies.  I've got them down to boards that are 1.16" (H) x

I got the HV sections and bias up and they work perfectly   Here's the board... I've already tested the GRLV boards and they work.  I just have to build another set for this supply. 

Here's the HV version set to 450v. Have to test this one still.

Posted Images

Sorry guys.
 
Yesterday I finished my second GRLV ready for 23,3volt but I have a problem. Rail + is ok with +23,37volt. but negative I only have -13,23volt.
 
I have some measures: 
 
w7nFNRK.jpg
 
7Mb72yE.jpg
 
I changed Q10 because I thought that it´s wrong but with a new Ksp42 I have the same values. The Led´s shine in the same way.
 
B9BeQnC.jpg
 
 
I do not know what is wrong. I suspect 15031 or 21193 but I'm not sure. Can you give me any recommendation?
 
Thanks... and happy new year :rolleyes:!!!!
 

 

Link to post
Share on other sites
On 12/29/2017 at 8:27 AM, luvdunhill said:

I would consider doing an assembled run of these, but we would need a decent amount of interest.

I'd be interested in some as well.

I presume these would have the same limitations in terms of voltage range as the normal GRLV does? Could you do 5V, etc. with these assuming the reference, etc. were changed?

Link to post
Share on other sites
11 hours ago, jose said:
 
 
7Mb72yE.jpg
 
 
 
 

 

It's difficult for me to ascertain from the photo but those diode boards orientation looks suspicious to me. 

Double check and make sure the board for the negative rail is mounted correctly.

Link to post
Share on other sites

Thanks guys! 

I know that it's unlikely the rectifier would be the problem given Jose is getting output just not the intended potential. I should have checked before I typed...

Does adjusting the negative rail trim pot do anything?

Edited by mwl168
Link to post
Share on other sites

I've just been learning Eagle.  They have a great integration to Fusion 360 since it was purchased by Autodesk.  

I've redone the GR78xx as my first test.  Still learning a lot, but getting there.

Here's some renderings after I pushed it to Fusion...

GR78xx_2018-Jan-01_02-33-01AM-000_CustomizedView23940028218_jpg.thumb.jpg.beebf9e1441905595732425d78598a7f.jpgGR78xx_2018-Jan-01_02-33-28AM-000_CustomizedView7863268940_jpg.thumb.jpg.cd5748cd445dda576c5ff1dff27f7eef.jpgGR78xx_2018-Jan-01_02-33-19AM-000_CustomizedView31521604338_jpg.thumb.jpg.932334d87b45a9631170349d60cd0eab.jpg

I've still got some work to do, but this looks very promising. Most things seem to be rendering properly, though the solder mask isn't coming over and the fonts seem off a bit. 

Once I have my boards in Eagle, I'll be able to drop the boards into my mechanical models.  I'm very excited :D 

PS  My plan was to use only three pins to connect to the main PS board.  Pins 1 & 5 are duplicates of 2 & 4.

  • Like 8
Link to post
Share on other sites

I remade my previous GRLV pcb for my amplifier:
1. Optimized the pcb size.
2. Fixed bugs of the previous version - added forgotten capacitors in the supply chain for op amps, the supply of all internal circuits takes from the pure part of the circuit, as in the original version of the board.
3. Now this is the native KiCad project, not the conversion from Eagle.

GerbersKiCad project3D view 

Link to post
Share on other sites

Thanks boys for replies. 

Yes, I use the ver. 0.44 so + is in front. I have before regulation -33Vdc. Maybe I can be wrong but I think that the bridge is OK but...

(By the way, Pars, thanks for the diode board)

 

PK4x9fw.jpg

 

ej6dUhx.jpg

Yesterday I was checking and cleaning up some things;

1. R9 and R10 it´s ok (2k and 1.5K). Identical values on both sides 

2. I changed Q2,Q10,Q13,Q11, Q5 (and D6 for try something)

With the same result. -13,23volt. 

3. I move trimpot (100K) but I haven´t any variation 

The first difference that I find between both rails is at the anode D6 (-14,9volt) and D4 (+15,64volt).

4. Volt in Pin2 and Pin3 (OPA134) is -10volt

This afternoon I will concentrate on the area of Q12, 1N914 and Trimpot. 

 

 

Link to post
Share on other sites
1 hour ago, jose said:

Yesterday I was checking and cleaning up some things;

1. R9 and R10 it´s ok (2k and 1.5K). Identical values on both sides 

2. I changed Q2,Q10,Q13,Q11, Q5 (and D6 for try something)

With the same result. -13,23volt. 

3. I move trimpot (100K) but I haven´t any variation 

The first difference that I find between both rails is at the anode D6 (-14,9volt) and D4 (+15,64volt).

4. Volt in Pin2 and Pin3 (OPA134) is -10volt

This afternoon I will concentrate on the area of Q12, 1N914 and Trimpot. 

 

 

it's a bit "odd" that you have -3.23V across the R9 (2k) (meaning 1.6mA), and at the same time 10V across R10 (1k5) (meaning  6.7mA) , so where does the remainder  5.1mA go? C3 as Kevin points to seems to be a reasonable guess ...provided that the 1Megs resistors are correct (which it seems from your pics), or the OpAmp itself ...

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...