09-18-2008 06:46 PM
09-18-2008 08:39 PM
09-18-2008 08:53 PM
09-18-2008 08:55 PM
You should be more careful with the schematic entry. For one thing you're applying -5VDC instead of +5VDC. Check the polarity of your batteries. It took some playing around with, but I got it working by using DGND (node 'GND') instead of AGND (node 0). There is a difference in SPICE!
Also, I'm not sure if it's intentional, but your LEDs are dropping a constant 1.6V and only 3.4 V is getting to the input lines of the 74LS47N. Seems to work regardless, though.
Let me know what I get for a grade.
-J
09-18-2008 08:57 PM
Kittmaster beat me to it 🙂
Swap out your 'GROUND' symbols with 'DGND'
09-18-2008 09:10 PM