Comments on: How to build a +5V regulator using 78L05 / 7805

By: Richard

Richard — Sun, 09 May 2010 20:03:17 +0000

Easy and effective; thanks for the tip.

By: czd

czd — Fri, 25 Dec 2009 05:49:46 +0000

Thank you for the article and schematic .. work perfect for me!

By: Stirplate power?

Stirplate power? — Wed, 18 Nov 2009 15:35:21 +0000

[...] http://stuff.nekhbet.ro/2006/06/18/how-to-build-a-5v-regulator-using-78l05-7805.html __________________ Quote: [...]

By: Tahir

Tahir — Fri, 23 Oct 2009 02:51:42 +0000

hey i want construct +/-5 volt supply please help me

By: building a mini +5v regulated power supply » ntsdt.net

building a mini +5v regulated power supply » ntsdt.net — Mon, 10 Aug 2009 02:59:46 +0000

[...] schematics available to produce a 5V dc regulated current, after searching around I found one at http://stuff.nekhbet.ro/2006/06/18/how-to-build-a-5v-regulator-using-78l05-7805.html. I used this as the basis for my design, but I also added a quick blow fuse to limit the amount [...]

By: Trimbitas Sorin

Trimbitas Sorin — Sat, 02 May 2009 11:35:29 +0000

No problem Paulor, glad I could help

By: paulor

paulor — Sat, 02 May 2009 11:22:53 +0000

Thanks Sorin,

That was it. Incredibly I did download a similar document and had a very good look at it until I was sure to be getting it right. It’s obvious I didn’t. So many trys and never swiched it because I was so sure to be doing it right. No heat for me meant everything fine. Only now I understand that it heats when you invert its polarity that is completely diferent. Thank you very much for even replying to a dum question like this but it really helped.

Best regards,
Paulor

By: Trimbitas Sorin

Trimbitas Sorin — Sat, 02 May 2009 06:58:48 +0000

Hi Paulor,

Are you sure you are connecting the 78L05 ok? Please take a look at http://www.national.com/ds/LM/LM78L05.pdf for pinouts.

Regards

Sorin

By: paulor

paulor — Sat, 02 May 2009 04:16:34 +0000

Hey,

I’ll start by saying I’m new to this.
I was trying to build my first power regulator circuit, followed a diagram and all seemed fine.

When testing, connected to a 9v battery (9,5v brand new) the circuit output was 8,9v representing a 0,6 v diference.
I checked all the circuit, replaced capacitors and the 78L05 as well just to be sure. Got the same result.
Lowering the input to 7,5v the power output had 6,9 wich represents the same 0,6v in diference.
After this I even tested it alone with no capacitors and got the same result.
What is happening here? Am I so unlucky I got two malfuncioning power regulators?
Is there any other possible explanation?

Thanks for any help.

By: Trimbitas Sorin

Trimbitas Sorin — Thu, 26 Mar 2009 18:00:50 +0000

WaiC .. you can use it exactly as 78L05 without any issues.

Regards

Sorin

By: WaiC

WaiC — Tue, 10 Mar 2009 16:35:18 +0000

Is it possible to use a LM7805CT to drive it? and what capacitance should i use for C1 and C2 if LM7805CT can be used?

By: Trimbitas Sorin

Trimbitas Sorin — Wed, 18 Feb 2009 05:54:46 +0000

Hi Ron,

The C1 and C2 are pretty important as they keep the 78L05 stable ( they have a tendency to oscillate in certain conditions ).

Hope this helps

Sorin

By: Ron

Ron — Sat, 14 Feb 2009 06:36:54 +0000

Hey Sorin,

Your power supply circuit works perfectly.Thanks a lot! I’m not a professional…so please dont mind if my questions sound a bit silly. Can you explain what exactly are the functions of the two capacitors connected at the input and output? If we dont use the caps, there seems to be drop in source voltage. Why is that?
Regards,
Ron.

By: Trimbitas Sorin

Trimbitas Sorin — Mon, 09 Feb 2009 10:14:53 +0000

Hi Wala,

Thank you for letting me know of this, I’ll upload it again in few seconds.

Best regards

Sorin

By: wala

wala — Wed, 07 Jan 2009 11:08:18 +0000

this reguletor data sheet was not be downloaded
by the server plese uload new data sheet