A controller is basically a unit present in a control system that generates control signals to reduce the deviation of the actual value from the desired value to almost zero or lowest possible value. It is responsible for the control action of the system so as to get accurate output. The method of producing a control signal by the controller is known as control action. The figure below represents the block diagram of an industrial controller: Basically the deviation of the achieved … [Read more...] about Types of Controllers
Examples of Closed-Loop Control System
We all know that a control system manages or directs the operation of a system in order to provide a specific output. In a closed-loop system, the desired output is achieved by making a comparison between achieved output and provided input. And for this purpose, a part of the output is fed back to the input in order to have the difference in the input and output value. This is known as a feedback signal. Thus we can say the system whose operation is controlled by its output is known as a … [Read more...] about Examples of Closed-Loop Control System
Closed-Loop Control System
Definition: A closed-loop control system is a type of control system in which the controlling action shows dependency on the generated output of the system. In simple words, in these systems, the output of the system controls the input applied to the system. The variation in input according to the output leads to produce more accurate system output. Thus controllability in the closed-loop system is achieved through the output generated by utilizing a feedback path. Closed-loop systems … [Read more...] about Closed-Loop Control System
Open-loop Control System
Definition: An open-loop system is a type of control system in which the output of the system depends on the input but the input or the controller is independent of the output of the system. These systems do not contain any feedback loop and thus are also known as non-feedback system. In open-loop systems, the output is neither measured nor fed back to the input for further consideration. Open-loop System In our previous article, we have discussed about control system. We know that a … [Read more...] about Open-loop Control System
Control System
Definition: A combination of various elements connected as a unit to direct or regulate itself or any other system in order to provide a specific output is known as a Control system. We know controlling is basically known as the act of regulating or directing. So control system is used to direct the functioning of a physical system to carry out the desired objective. For example, from a television system, refrigerator, air conditioner, to automobiles and satellites everything needs a … [Read more...] about Control System
Programmable Logic Array (PLA)
Definition: Programmable Logic Array, abbreviated as PLA is a programmable logic device having programmable AND gates and OR gates. These devices are basically programmed to implement the Boolean functions. The fundamental components of PLAs are input buffer, programmable AND gate matrix and programmable OR gate matrix. PLA allows the implementation of any random boolean function present in SOP form using programmable technique. Components of PLA Input Buffer: Basically buffers at the … [Read more...] about Programmable Logic Array (PLA)
Shift Register
Definition: A shift register is a sequential logic circuit that acts as a unit to store and transfer binary data. Basically shift registers are bidirectional FIFO circuit, that shifts every single bit of the data present in its input towards its output on each clock pulse. We know registers are the circuits constructed using flip-flops for storing binary data. One-bit of data is stored by each flip-flop at a time. So, the storage of multiple bits of data requires multiple flip-flops. Thus … [Read more...] about Shift Register
Freewheeling (Flyback) Diode
Definition: Freewheeling diode is used to protect the circuit from unusual damage caused due to abrupt reduction in the current flowing through the circuit. It is also known as Flyback diode and forms connection across the inductor to remove Flyback voltage generated across it. Freewheeling diodes are also known as kickback diode, clamp diodes, commutating diodes, suppression diodes, or snubber diode etc. Here in this article, we will discuss the factors responsible for the need of such … [Read more...] about Freewheeling (Flyback) Diode
Digital Comparator – Magnitude and Identity Comparator
Definition: A Digital Comparator is a combinational logic circuit that is used for comparison of two binary values. Basically it generates the desired signal (either low or high) at the output when compares two digital values provided at its input. We all know that combinational circuits (like adder and subtractor) produce addition and subtraction of binary values present at the input terminals. But, along with addition and subtraction, some applications require a comparison of two values … [Read more...] about Digital Comparator – Magnitude and Identity Comparator
Phase-Locked Loops (PLL)
Definition: Phase-locked loops are the circuits used to maintain synchronization between input and output frequency of oscillator circuits by comparing the difference in phase of the two signals. With the evolution of IC, it has emerged as the basic building block of electronic circuits. Phase-locked loops are abbreviated as PLL and are basically a feedback circuit comprising of a phase detector (or comparator), a low pass filter and voltage-controlled oscillator along with an … [Read more...] about Phase-Locked Loops (PLL)