# Simple logic diagram help!! please

Discussion in 'Homework Help' started by abcd1234, Sep 28, 2006.

1. ### abcd1234 Thread Starter New Member

Sep 28, 2006
1
0
Hi,

For part of my project I had to create a logic diagram with 4 outputs. I was able to plot 3 outputs but could not graph the last one which is:

y = AC(B'+D')

Couls someone help me out? Also, what is the difference between a logic diagram and a pin-out diagram?

THANKS!

2. ### Papabravo Expert

Feb 24, 2006
10,340
1,850
Use DeMorgan's Law as follows
AC(B'+D') = AC(BD)'

That last expression requires a three input AND and a two input NAND
or
Three two input AND gate and an inverter

3. ### Dave Retired Moderator

Nov 17, 2003
6,960
145
A logic diagram shows the layout of the logic components that constitute your circuit, i.e. in terms of AND, OR, NOT, NOR, XOR etc gates. The pinout diagram shows the pin allocations for a particular package that is used in your circuit, i.e. a topological representation.

From the logic diagram you can deduce functionality but not implementation, whereas in a pinout diagram you can deduce implementation but not necessarily functionality.

Dave