Digital Logic

• AND gate will only output a positive signal if both A and B are 1

  
• A truth table is used to record the outcomes of a logic operation where Z is the output and A, B, C (etc) are the inputs

  
• A Boolean Expression is used to represent a symbol diagram
• This is the Boolean Expression for a NOT gate

  
• This is the Boolean Expression for an AND gate

  
• This is the Boolean Expression for an OR gate

  
• A NOT gate will invert the signal sent through it

  
• An OR gate will only output a positive signal if one or both of the inputs are positive.

  
• AND gate will only output a positive signal if both inputs are positive