Here is what my textbook has to say about logic levels:
The mapping of a continuous variable onto a discrete binary variable is done by defining logic levels. […] The first gate is called the driver and the second gate is called the receiver. The output of the driver is connected to the input of the receiver. The driver produces a LOW (0) output in the range of 0 to VOL or a HIGH (1) output in the range of VOH to VDD. If the receiver gets an input in the range of 0 to VIL, it will consider the input to be LOW. If the receiver gets an input in the range of VIH to VDD, it will consider the input to be HIGH. If, for some reason such as noise or faulty components, the receiver’s input should fall in the forbidden zone between VIL and VIH, the behavior of the gate is unpredictable. VOH, VOL, VIH, and VIL are called the output and input high and low logic levels.
(Digital Design and Computer Architecture – David Harris and Sarah Harris)
Since it seems that the driver itself is able to convert continuous analogue values to discrete ones (HIGH and LOW). Why do we need the receiver as well?
Thank you!
Best Answer
The driver is the output of one logic gate (or flip-flop or other logic devices), and the receiver is the input of another logic gate.
In any system using digital logic, you will have many logic circuits interconnected, with each interconnection having a driver and one or more receivers.
In that description, the driver and receiver are not parts of a single device.