On Wed, 09 Dec 2009 15:08:15 +1300, you wrote:
>Another point is the LTSpice LED model isn't particularly accurate for >simulating the effects of temperature variations. >Does anyone knows of more accurate LTSpice compatible LED models? > >The LED model voltage drop increases with temperature even at low >current, whilst the voltage drop across a real LED at low currents >decreases with temperature. >In practice the variation in the LED forward drop tracks the variation >in the pnp Vbe quite well. I have used this model and also this diode: * from OSRAM TOPLED library * * .MODEL LH_T676_typ D + IS=5.5621E-24 + N=1.3448 + RS=4.3842 + IKF=17.186E-3 Comparing the current with a BC860 PNP and a 15 Ohm emitter resistor worked quite nicely, so I had no reason to investigate the model. (as you wrote, too) I also tried to operate a power LED with the base bias divider current of all 6 distribution channels combined(70 mA tot.) to recycle the current but it seemed that the power LED had more Ohmic resistance than 6 times LHT676. Could be just my sample, and it was close to the max. specs. Gerhard _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
