11-15-2013, 06:58 AM
claudef,
There's something wrong with that drawing, or I'm misinterpreting it. Pins 4, 5, 9 and 10 are all inputs to NAND gates with nothing driving them so you have floating inputs with the NAND gate outputs driving the LED. Not a good thing. I think those four pins need to be connected to the other NAND gate inputs, pins 1, 2, 12 and 13.
The other thing using that particular IC is that the outputs will likely be fighting each other. It would be better to use an IC with open collector outputs. I would just use a transistor instead of an IC though.
Ed
There's something wrong with that drawing, or I'm misinterpreting it. Pins 4, 5, 9 and 10 are all inputs to NAND gates with nothing driving them so you have floating inputs with the NAND gate outputs driving the LED. Not a good thing. I think those four pins need to be connected to the other NAND gate inputs, pins 1, 2, 12 and 13.
The other thing using that particular IC is that the outputs will likely be fighting each other. It would be better to use an IC with open collector outputs. I would just use a transistor instead of an IC though.
Ed