This subject covers operational amplifier principles and applications including comparators (zero and non-zero crossing detectors), voltage followers, inverting and non-inverting amplifiers. Subtraction, summing (mixer) difference and compound amplifiers and active filters. Operational amplifiers circuits are configured to make up complex analog circuits. It includes the temperature controller and the pulse width modulation technique of DC motor speed control. The importance of digital computers used in modern industrial processes is stressed. Thyristors, photosensitive devices, optically coupled devices, timer control circuits and various transducers are introduced.
