Logic gates
===========
Logic gate circuits can perform operations like AND, OR etc. They can be implemented using
PN junction diodes for demonstration purpose. A wide range of logic gate ICs are also available. 

**Objective**

Study of logic gates using SQ1 and PV1 as inputs, using TTL logic ICs
7408 and 7432.

**Procedure**

.. image:: schematics/gate-or-diode.svg
	   :width: 300px

.. image:: schematics/gate-and-ic.svg
	   :width: 300px

-  On a bread board, wire one of the circuits shown above.	   
-  Enable A1, A2 ands A3. Set input range on A1 and A2 to 16V
-  Set SQ1 to 500 Hz and WG to 1000 Hz
-  Select SQ2 from the WG wave shape
-  Shift the traces using the vertical sliders on the left, for better view.

The results for the OR gate made using the diodes is shown below.

.. image:: pics/gate-or-diode-screen.png
	   :width: 500px

The results for the AND gate made using the IC 7408 is shown below.

.. image:: pics/gate-and-ic-screen.png
	   :width: 500px

**Discussion**

The working of the logic gate will be evident from the 3 waveforms. You
may shift traces vertically to separate them for clarity.
