Red LED noise.

[GK]

G'day.

Anyone out there know how noisy red LED's are as voltage references?

Cheers,
Glen

[Christer]

For what it's worth, I did some measurements on various voltage references a while ago in this thread. See the attachment in this post for the "final" results.

[GK]

Originally posted by Christer
For what it's worth, I did some measurements on various voltage references a while ago in this thread. See the attachment in this post for the "final" results.

Fantastic! Thanks for that.

Cheers,
Glen

[Nelson Pass]

Yes, thanks. That is very useful information.

[Leolabs]

Many many thanks!

[lineup]

Originally posted by john curl

Great work, Christer!
How about different color leds from the same family of devices?
Did I miss this in reading this thread?

You have a great test rig. Just plug in a red, yellow and green one at two ma, and compare.
You will have my appreciation, (to save me from doing this).
.

Originally posted by lineup

Hello, all serious noise level 'care-about-diyaudio-builders'
it is time for a

Mister John Curl BUMP

as you probably wouldn't be very much impressed
by
a lineup bump
Your own fault - you may be missing something!

no harm to john curl - he has shown me some good things
I have learned a lot from

Thanks John!
I never forget.
_______
by lineup on 6th September 2006 at 01:14

Originally posted by lineup

Christer has provided noise figures for BC550 transistors, as well.
At different currents. Something like 2-3 mA was found to be a good value to use
for minimal noise figures.

Now an Amplified Diode using for example BC550
would probably have similiar noise values, but a bit higher
depending how high the voltage would be.

The Amplified diode has got a total voltage
which is a factor of the transistor vBE, set by 2 resistors.


lineup
Lineup Transistor Lab
_______
by lineup 7th October 2006 16:08

#########################################

Originally posted by Nelson Pass

Yes, thanks. That is very useful information.

#########################################


... and my first post, Post #75
in this Christer Topic
was already in
21st January 2006 20:10

Originally posted by lineup

Download: Noise Measurements 1.4 by Christer

This topic deserves to be STICKY in forum.
It is very useful for designing low noise amplifiers,
voltage regulators and
other audio circuits.
------
Take Red LED at 5 mA
Measures: 0.27 uV and LED Voltage is 1.89 Volt.
.

the above my first post, Post #75
in this Christer Topic
was already in
21st January 2006 20:10



==============================================
Now people,
if you are
deaf,
plain stupid or
just ****** ignorant,
I do not care which, frankly,
but you should know one thing,
about lineup:
.... when he says something 1 time, he usually have a good point
he wants to share with you
.... when he says something 2 times, he is bothered someone did not get his point 1st time
.... when he says something 3 times, he is usually getting highly annoyed someone did not listen 2nd time
.... when he says something 4 times or more, he has really found something very valuable
and kindly begs you to listen, notice and have a closer look

Because he does not want you to miss - what he has found is good
==============================================

Regards
lineup for the 5th time
recommending his fellow countryman Christer's work

PS. If you do not take my word for it or
you are not too bothered what Mister John Curl thinks
...
at least listen to Mister Nelson Pass
...
because he doesn't talk too much
.. as little me, Mister lineup, certainly can do
.. but not too often, I hope. DS.