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
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
Attachments
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.../+leds+spice+models&hl=it&gl=it&ct=clnk&cd=10
(cache copy because this site is unavailable)
bye
for best spice model
also look this document... http://72.14.221.104/search?q=cache.../+leds+spice+models&hl=it&gl=it&ct=clnk&cd=10
(cache copy because this site is unavailable)
bye
Gold_xyz said: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.../+leds+spice+models&hl=it&gl=it&ct=clnk&cd=10[/url]
(cache copy because this site is unavailable)
bye
Thanks,
Gold_xyz
I go have a look.
Hi lineup
I have also found other links...
http://www.orcad.com/documents/community.an/pspice/tn27.aspx
http://www.cadence.com/appnotes/ModelingPhotodiodesLEDsandLaserDiodes.zip
http://www.edn.com/article/CA60961.html
Bye
I have also found other links...
http://www.orcad.com/documents/community.an/pspice/tn27.aspx
http://www.cadence.com/appnotes/ModelingPhotodiodesLEDsandLaserDiodes.zip
http://www.edn.com/article/CA60961.html
Bye
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.