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Digital Electronics

Digital electronics 

A digital system includes an input sensor and a processor circuit, which controls the voltage to an output device. 

The processor circuit consists of a series of logic gates. Logic gates respond to small voltages which are either on or off. They do not respond to analogue signals. 

  • An analogue signal (V) varies continuously in amplitude 
  • A digital signal (V) has only two states: High or low (or on and off, or 1 and 0) 

 

Logic gates

Logic gates transform a digital input voltage into an output, which depends on the type of logic gate.

The input voltages are given as 1 or 0 (on or off) and the input/output of these logic gates can be represented on a truth table. 

  • A NOT gate gives an output that is opposite of the input 
  • An AND gate only gives an output if the input A and B are both 1 
  • An OR gate gives an output if input A or input B is 1 

Logic gates can be combined to perform different functions in various electric circuits.