DIGITAL ELECTRONICS
Lecture-1
Introduction to Digital and Analog Signals
To transmit information, two types of signals are used; analog and digital. Both types of
signals not only have different properties but also function differently.
Analog signalling
This is the classic method of signalling. In this method, signals move like waves. The sending
device converts data into waves and loads those waves on the media. The receiving device
picks up those waves from the media and converts them back into the data.
Digital signaling
This is the modern method of signalling. In this method, signals are transmitted in binary
form as pulses. In binary form, information is stored by using two types of bit; on bit and off
bit.
To transmit both types of bits, two types of pluses are used in digital signalling; a pulse of
positive voltage and a pulse of zero voltage. Both pulses are represented as on bit (1) and off
bit (0) respectively.
To transmit a binary bit, an individual pulse is used. In other words, every pulse in digital
signals represents a signal binary bit.
Analog Signals DIFFERENCE Digital Signals
Continuous, Discrete
Infinite range of values, Finite range of values
More exact values, Not as exact as analog,
but more difficult to work with but easier to work with
Advantage of Digital Signal over Analog
Usually the transmission of digital signals is much more robust to noise or interference
corruption than analog signals. The same applies to their storage.