Amplifier Input CSS, good thermal data + Red LED model

[lineup]

hello


CCS in Amplifier with low thermal drift + Red LED spice model

Red LED is very good and useful for CSS, constant current sources, in amps.
If, for example, placing a Flat Red LED into close thermal contact with a TO92 Transistor
you get almost perfect thermal compensation.
And the CSS keep the current very constant.

For an Amplifier input differential stage this is a very good thing.
Especially when we need low offset and best performance at high/medium voltage gains.
Because if CCS will deviate, then also offset will change.

RED LED also makes a low noise voltage reference in these CCS,
if used with a Diode Current of like 2 - 5 mA.



See my attachment drawing
for one such very good constant current source.
========================================

My problem is that in my Simulation Software, I have no good spice model.
The RED LED that comes with Electronics Workbench Multisim,
has only one voltage 1.66V, whatever current I put into the LED.
This is bad! You would expect better from an advanced commercial spice software.


I want to have a good model for a normal standard RED LED. (there are many types)
Those you can buy 100 pieces of, for a low price.


lineup

[Gold_xyz]

You can try to ask at vishay http://www.vishay.com/leds/
for best spice model
also look this document... http://72.14.221.104/search?q=cache:...&ct=clnk&cd=10
(cache copy because this site is unavailable)

bye

[lineup]

Originally posted by Gold_xyz
You can try to ask at vishay http://www.vishay.com/leds/
for best spice model
also look this document... http://72.14.221.104/search?q=cache:...clnk&cd=10</a>
(cache copy because this site is unavailable)

bye

Thanks,
Gold_xyz

I go have a look.

[Gold_xyz]

Hi lineup

I have also found other links...
http://www.orcad.com/documents/commu...pice/tn27.aspx
http://www.cadence.com/appnotes/Mode...aserDiodes.zip
http://www.edn.com/article/CA60961.html


Bye