Category: Interfacing with Microprocessors

Temperature Control System

Temperature Control System: Before going to study the temperature control system, let us see the block diagram of microprocessor based process Temperature Control System. It is capable of controlling more than one physical parameter. Such systems are commonly known as data acquisition and control systems. In these system, analog signals from various sensors are converted […]

Speed Control of DC Motor

Speed Control of DC Motor: The Fig. 15.38 shows the analog approach to control the Speed Control of DC Motor. A tachometer is used to get the information about the Speed Control of DC Motor. It is a DC generator mounted on the shaft of the DC motor. It gives the output voltage proportional to […]

Sensors and Transducers

Sensors and Transducers: The definition of┬áSensors and Transducers are follows, The input quantity for most instrumentation systems is nonelectrical. In order to use electrical methods and techniques for measurement, the nonelectrical quantity is converted into a proportional electrical signal by a device called “transducer”. Actually, electrical transducer consists of two parts which are very closely […]

Process Control Block Diagram

Process Control Block Diagram: The primary objective of industrial process control is to control physical parameters such as temperature, pressure, flow rate, level, force, light intensity, and so on. The Process Control Block Diagram is designed to maintain these parameters near some desired specific value. As these parameters can change either spontaneously or because of […]

Interfacing Dip Switch

Interfacing Dip Switch: A series of tiny switches built into circuit board and the housing for which has a same shape as chip are known as DIP switches. The Fig. 15.23 shows the Interfacing Dip Switch housing with 11 switches. DIP switches enable you to configure a circuit board for a particular type of computer […]

Optical Encoders

Optical Encoders: The Optical Encoders are used to get the information about the position, direction of rotation, and speed of rotation of various motor shafts. They provide this information in digital form which can easily be used by microcomputers to control the speed, direction of rotation and position of the motor shaft. There are two […]

Solid State Relay Interfacing

Solid State Relay Interfacing: To avoid the problems of mechanical relays, Solid State Relay Interfacing are used. In this triac is used as a switching element and isolation is provided by opto isolators or pulse transformer. The Fig. 15.16 shows the typical opto isolator circuitry. It consists of LED and a photo transistor. LED glows […]

Electromagnetic Interference

Electromagnetic Interference: To control ON/OFF operation of ac devices we can use electromagnetic relay. This relay has both normally open and closed contacts. When a current is passed through the coil of the relay, the switch arm is pulled down, opening the top contact and closing the bottom contact, as shown in the Fig. 15.15 […]

Stepper Motor Interface

Stepper Motor Interface: A stepper motor is a digital motor. It can be driven by digital signal. Fig. 15.18 shows the typical 2 phase Stepper Motor Interface using 8255. Motor shown in the circuit has two phases, with center-tap winding. The center taps of these windings are connected to the 12V supply. Due to this, […]

Transistor Buffer Circuit

Transistor Buffer Circuit: The Fig. 15.12 shows the Transistor Buffer Circuit. In these Transistor Buffer Circuit, transistor is used as a switch. It can be switch ON or OFF with logic 0 or logic 1 on port pin depending on the application. To make transistor ON with logic 0 at port pin we have to […]