Author |
Message |
Gaetano_AU
Joined: Oct 08, 2011 Posts: 64 Location: Australia
|
Posted: Thu Jan 10, 2013 4:05 pm Post subject:
Simple 78xx (Positive)and 79xx (Negative) Power Supply Subject description: A Simple Power Supply using a easily available protoboard. |
|
|
I needed a simple fixed dual rail power supply for a project, so I made this on a stripboard. I used a 'Stripboard - Small': Part Code: 'STPBRD2' which you can easily get from Futurlec.
http://futurlec.com/Protoboards.shtml
or
http://www.futurlec.com.au/ProtoBoards.jsp
To give credit where it's due. After I finished it, I opened Thomas Henry's books which I just received, and the first thing I saw was the power supply, in 'An Analog Synthesizer for the 21st Century'. So I added Diodes D7 & D8 for further protection.
All diodes are standard Silicon 1N4004.
Description: |
The underside of the board with heat-sinks and the regulators vertically mounted. |
|
Filesize: |
240.51 KB |
Viewed: |
382 Time(s) |
This image has been reduced to fit the page. Click on it to enlarge. |
|
Description: |
With heat-sinks and the regulators vertically mounted as the board is quite small, you can pull a larger current. I would in addition put some extra tinned wire underneath where needed. In an etched PCB the tracks would be thicker there. |
|
Filesize: |
200.88 KB |
Viewed: |
381 Time(s) |
This image has been reduced to fit the page. Click on it to enlarge. |
|
Description: |
|
Filesize: |
242 KB |
Viewed: |
351 Time(s) |
This image has been reduced to fit the page. Click on it to enlarge. |
|
Description: |
If you do not want to pull a large current say < 200mA, you can just lay the regulators flat or for 100mA use 78Lxx and 79Lxx 100mA regulators, but the TO-220 versions are more robust and about the same cost (shown here). |
|
Filesize: |
204.69 KB |
Viewed: |
367 Time(s) |
This image has been reduced to fit the page. Click on it to enlarge. |
|
Description: |
|
Filesize: |
51.3 KB |
Viewed: |
440 Time(s) |
This image has been reduced to fit the page. Click on it to enlarge. |
|
Last edited by Gaetano_AU on Sat Apr 20, 2013 1:41 am; edited 5 times in total |
|
Back to top
|
|
|
baudrate
Joined: Mar 19, 2012 Posts: 27 Location: Utah
|
Posted: Fri Jan 11, 2013 9:39 am Post subject:
|
|
|
Would it be a good idea add heat sinks to the 78xx and 79xx? |
|
Back to top
|
|
|
Gaetano_AU
Joined: Oct 08, 2011 Posts: 64 Location: Australia
|
Posted: Fri Jan 11, 2013 5:28 pm Post subject:
|
|
|
Yes if you pull a large current, say you wanted to use > 200mA on each rail, I definitely would. I mentioned that under 'Parts Overlay', where if you did do this you would probably also need to run heavier wires underneath to the diodes and out from the regulators as you approach 1A. Otherwise you don't need to for a few filters. For a few low power circuits, you could actually use 78Lxx and 79Lxx 100mA regulators, but I don't see the point in using these, when these TO-220 1A versions are about the same price, and way more robust. |
|
Back to top
|
|
|
mirri
Joined: Mar 29, 2009 Posts: 13 Location: Finland
|
Posted: Wed Apr 17, 2013 3:57 am Post subject:
|
|
|
Hello and thanks for this, i noticed a small error i think? D7 seems to be connected to a strip that isn't used. Or did i understood the schematics incorrectly?
/m |
|
Back to top
|
|
|
PHOBoS
Joined: Jan 14, 2010 Posts: 5591 Location: Moon Base
Audio files: 705
|
|
Back to top
|
|
|
Gaetano_AU
Joined: Oct 08, 2011 Posts: 64 Location: Australia
|
Posted: Wed Apr 17, 2013 5:27 am Post subject:
|
|
|
Yes, it was a sort of typo, D7 has now been fixed on the board overlays above. The circuit works fine, it was a prototype for a simple +-10v PCB board I later made for a MiniMoog VCF Clone. |
|
Back to top
|
|
|
mirri
Joined: Mar 29, 2009 Posts: 13 Location: Finland
|
Posted: Wed Apr 17, 2013 5:29 am Post subject:
|
|
|
Ok, thanks! |
|
Back to top
|
|
|
|