The post Introduction to logic gates appeared first on projectiot123 Technology Information Website worldwide.

]]>Digital systems have been gaining attention for the last few decades due to their benefits over analog circuits. Digital Circuits are less prone to noise and signal processing in digital domain is better than in analog domain. The digital logic gates are fundamental building blocks of the Digital Circuit. These logic gats can be wired in variety of ways to perform the particular task. The three basic digital logic gates are:

These basic digital logic gates can be connected in peculiar ways to form other important logic gates. Logic gates formed by the peculiar combination AND, OR and NOT are:

Here the basics of all these logic gates are discussed. Before we start discussion it is important to mention that each basic logic gate implements a particular Boolean operation and these basic logic gates can be connected to implement complex Boolean expressions.

AND Gate perform the Logic AND operation. Basic AND Gate has two inputs and a single output. The relationship between the inputs and output of the AND Gate is represented by Boolean AND function. The following image shows the truth table, schematic symbol and Boolean Expression of AND Gate.

The AND Operation is represented by . sign. The Output of the AND Gate is HIGH if and only if both of its inputs are HIGH.

OR Gate performs the Logic OR operation. Basic OR Gate has two inputs and a single output. The relationship between the inputs and output of the OR Gate is represented by Boolean OR function. The following image shows the truth table, schematic symbol and Boolean Expression of OR Gate.

The OR Operation is represented by + sign. The Output of the OR Gate is HIGH if one of the inputs of the OR Gate is HIGH or both of the inputs are HIGH otherwise its output is LOW.

NOT Gate is the simplest logic gate with single input and single output. NOT Gate is also referred to as INVERTER and implements the logic NOT Operation. The truth table, schematic symbol and Boolean expression of the NOT Gate are as shown in the following figure:

The Output of the NOT Gate is the complement of its input which is represented by the bar symbol. The output will be HIGH when the input is LOW and vice versa.

NAND Gate is formed by connecting output of the AND Gate at the input of the NOT Gate. Thus the NAND Gate is the negation of the AND Gate. The truth table, schematic symbol and Boolean Expression of the NAND Gate are as shown in the following figure:

The output of the NAND Gate is LOW if and only if both of its inputs are HIGH otherwise the output is HIGH. Note that the truth table of the NAND Gate is complement of the AND Gate.

NOR Gate is formed by connecting output of the OR Gate at the input of the NOT Gate. Thus the NOR Gate is the negation of the OR Gate. The truth table, schematic symbol and Boolean Expression of the NOR Gate are as shown in the following figure:

The output of the NOR Gate is HIGH if and only if both of its inputs are LOW otherwise the output is LOW. Note that the truth table of the NOR Gate is complement of the OR Gate.

The XOR Gate is formed by connecting the AND, NOT and OR in particular configuration. XOR Gate is the two input and single output logic gate. The truth table, schematic symbol and Boolean expression the XOR Gate is as shown in the following figure:

The Output of the XOR Gate is HIGH when both of its inputs are different otherwise the output is LOW. The XOR Gate is commonly used in Full Adder, Half Adder circuit. The XOR Gate is also used in the comparator circuit.

Like XOR Gate XNOR Gate is also formed by the combination of basic Gates. XNOR Gate is the complement of the XOR Gate. The truth table, schematic symbol and Boolean Expression of the XNOR Gate is as shown in the following figure:

The output of the XNOR Gate is HIGH if and only if both of the inputs are same otherwise the output is LOW. Note here that the truth table of the XNOR Gate is the complement of the XOR Gate.

That is all for now, I hope this article would be helpful for you. In the next article I will come up with more interesting topics. Till then stay connected, keep reading and enjoy learning.

The post Introduction to logic gates appeared first on projectiot123 Technology Information Website worldwide.

]]>The post Introduction to XNOR Gate appeared first on projectiot123 Technology Information Website worldwide.

]]>

NOR Gate is formed by the combination of OR and NOT Gate in series that is by connecting the output of the OR at the input of the NOT Gate similarly NAND Gate is formed by the combination of AND and NOT Gate. Other important Gates formed by the combination of basic logic gates are XOR (Exclusive OR) and XNOR (Exclusive NOR) Gates. XOR and XNOR are formed by connecting AND, NOT and OR in particular configuration; we will see later that XOR or XNOR Gate can be formed in a variety of ways. Here the discussion in oriented to XNOR Gate only.

XNOR Gate also referred to as Exclusive NOR Gate is a digital logic Gate formed by combining three basic gates that is AND, OR and NOT Gates in a particular configuration. XNOR Gate is a two input single output digital logic gate although it can also be configured for multi inputs. XNOR Gate operates on the inputs in such a way that the network of AND, OR and NOT processes the inputs and generates the output according to the Boolean expression representing the XNOR Gate. The following image shows the schematic symbol and basic network configuration for the XNOR Gate.

The XNOR operation is represented by the sign. Notice in the image that unlike NAND Gate and NOR the exclusive NOR Gate consist of the comparatively complex network to realize the XNOR operation. The Boolean expression representing the XNOR Gate functionality is as shown in the following figure:

Notice that the XNOR functionality can be represented by two Boolean expressions. Other Boolean expression can be derived by using the De Morgan’s Theorem. Each Boolean expression is equivalent to the other and thus it implies that XNOR Gate can be implemented by multiple configurations. Recall from the discussion on NAND Gate and NOR Gate that being universal Gates they can also be used to implement the Boolean expression of XNOR Gate. Thus it concludes that multiple configurations can be employed to realize XNOR Gate functionality. The Boolean Expressions along with their circuit implementation of XNOR Gate are shown in the following image.

The Boolean expression on the left is called the product of sum and other expression derived from the DeMorgan’s Theorem is called as Sum of product.

The relation between the state of the output variable and that of the input variables is represented in the form of the table. This table is called the Truth Table. The Truth Table of the XNOR Gate along with its schematics symbol is shown below:

The output of the XNOR (Exclusive OR) Gate is HIGH if and only if both of the inputs A and B of the XNOR are HIGH otherwise the output will be LOW. Note that the output of the XNOR Gate is HIGH when its inputs are same, for different inputs the output is LOW thus the XNOR Gate can be said to detect the equality of input variables. Also note from the truth table that the output of the XNOR Gate is the exact complement of the XOR Gate.

The Boolean function of XNOR Gate is very important that makes XNOR Gate very useful in digital systems. Although XNOR Gate can be used in a variety of applications one of the most common and simplest applications of XNOR Gate is its use in Full Adder circuit. XNOR Gate in combination to other basic gates can be wired to form Full Adder circuit. The circuit of Full Adder using XNOR Gate is as shown in the following image.

Full Adder performs the binary addition on binary inputs. As shown in the circuit above the full adder has three inputs A, B and CarryIN and two outputs SUM and CarryOUT. The XNOR Gate can also be used to design the comparator due to its unique truth table. The equality comparator using XNOR (Exclusive Gate) is shown in the following figure.

** **

** **

** **

XNOR gates are available in the IC packages. The TTL (Transistor-Transistor Logic) and CMOS (Complementary Metal Oxide Semiconductor) technology is used to designed XNOR gate. One of the most popular IC for XNOR Gate is 74HC266N which is a QUAD two inputs XNOR Gate IC which means that this IC contains four independent two input XNOR Gates. The pinout and connection diagram of the 74HC266N IC is shown below:

That is all for now I hope this article would be useful for you. In the next article I will come up with more interesting topics. Till then stay connected, keep reading and enjoy learning.

The post Introduction to XNOR Gate appeared first on projectiot123 Technology Information Website worldwide.

]]>The post Introduction to XOR Gate appeared first on projectiot123 Technology Information Website worldwide.

]]>- AND Gate.
- OR Gate.
- NOT Gate.

AND Gate implements the Boolean AND function, OR gate implements the Boolean OR function and likewise NOT Gate (also called Inverter) implements the Boolean NOT function. The Boolean expressions of each basic gate along with their schematics symbol are shown in the following figure.

The input and output variables of the Boolean function can assume any one of two possible values called ‘0’ or ‘1’. In terms of positive logic ‘0’ is considered to be low and ‘1’ is considered to be HIGH, whereas in terms of the negative logic ‘0’ is considered to be HIGH and ‘1’ is considered to be LOW. Any Boolean expression can be implemented using these three basic logic Gates.

These basic digital logic gates that is AND, OR and NOT gates can be combined together in particular topologies to realize other important gates. The most common examples are NAND and NOR Gate. NOR Gate is formed by the combination of OR and NOT Gate in series that is by connecting the output of the OR at the input of the NOT Gate similarly NAND Gate is formed by the combination of AND and NOT Gate. Other important Gates formed by the combination of basic logic gates are XOR (Exclusive OR) and XNOR (Exclusive NOR) Gates. XOR and XNOR are formed by connecting AND, NOT and OR in particular configuration; we will see later that XOR or XNOR Gate can be formed in a variety of ways. Here the discussion in oriented to XOR Gate only.

XOR Gate also referred to as Exclusive OR Gate is a digital logic Gate formed by combining three basic gates that is AND, OR and NOT Gates in a particular configuration. XOR Gate is a two input single output digital logic gate although it can also be configured for multi inputs. XOR Gate operates on the inputs in such a way that the network of AND, OR and NOT processes the inputs and generates the output according to the Boolean expression representing the XOR Gate. The following image shows the schematic symbol and basic network configuration for the XOR Gate.

The XOR operation is represented by the ⊕ sign. Notice in the image that unlike NAND Gate and NOR the exclusive OR consist of the network to realize the XOR operation. The Boolean expression representing the XOR Gate functionality is as shown in the following figure:

Notice that the XOR functionality is represented by two Boolean expressions. Each Boolean expression is equivalent to the other and thus it implies that XOR Gate can be implemented by multiple configurations. Recall from the discussion on NAND Gate and NOR Gate that being universal Gates they can also be used to implement the Boolean expression of XOR Gate. Thus it concludes that multiple configurations can be employed to realize XOR Gate functionality. The Boolean Expressions along with their circuit implementation of XOR Gate are shown in the following image.

The equivalence of the two expressions can be verified using DeMorgan’s LAW. The Expression on the left is called product of sum and that on right is called sum of product.

The relation between the state of the output variable and that of the input variables is represented in the form of the table. This table is called the Truth Table. The Truth Table of the XOR Gate along with its schematics symbol is shown below:

The output of the XOR (Exclusive OR) Gate is HIGH if and only if one of the inputs A and B of the XOR is HIGH otherwise the output will be LOW. Note that the output of the XOR Gate is HIGH when its inputs are different for same inputs the output is LOW thus the XOR Gate can be said to detect the equality of input variables.

The Boolean function of XOR Gate is very important that makes XOR Gate very useful in digital systems. Although XOR Gate can be used in a variety of applications two most common and simplest applications of XOR Gate is its use in Half Adder and Full Adder. XOR Gate in combination to other basic can be wired to form Half Adder and Full Adder circuit. The circuits of Half Adder and Full Adder using XOR Gate are shown in the following image.

Half Adder and Full Adder perform the binary addition on binary inputs. The XOR Gate can also be used to design the comparator due to its unique truth table. In case of Half Adder the XOR solely can represent the sum two inputs binary variables the AND Gate is used to give the Carry bit. S represents the sum and C represents the Carry bit.

The equality comparator using XOR (Exclusive Gate) is shown in the following figure.

XOR gates are available in the IC packages. The TTL (Transistor-Transistor Logic) and CMOS (Complementary Metal Oxide Semiconductor) technology is used to designed XOR gate. One of the most popular IC for XOR Gate is 7486 which is a QUAD two inputs XOR Gate IC which means that this IC contains four independent two input XOR Gates. The pinout and connection diagram of the 7486 IC is shown below:

That is all for now I hope this article would be useful for you. In the next article I will come up with more interesting topics. Till then stay connected, keep reading and enjoy learning.

The post Introduction to XOR Gate appeared first on projectiot123 Technology Information Website worldwide.

]]>The post Introduction to NOR Gate appeared first on projectiot123 Technology Information Website worldwide.

]]>As pointed out in previous paragraph that NOR Gate is the combination of OR and NOT Gate with input of NOT Gate connected at the output of the OR Gate. Thus corresponding to each combination of the inputs of the NOR Gate, it will have an output that is the complement of the output of the OR Gate. The schematic symbol along with the basic circuit of the NOR Gate is as shown in the following image:

As shown in the image above NOR Gate process the inputs A and B in such a way that first OR Gate manipulates the input variables A and B to generate A+B and then NOT gate acts on A+B to generate complement of the A+B. The Bubble symbol at the OR gate represents the negation of the output of the OR Gate.

The relation between the state of the output variable and that of the input variables is represented in the form of the table. This table is called the Truth Table. The Truth Table of the NOR Gate along with its schematics symbol is shown below:

The output of the NOR Gate is HIGH if and only if both of its inputs are LOW otherwise its output is LOW, note that the output of the NOR Gate is exact complement of the output of the OR Gate in which output will be LOW if only if both inputs are LOW otherwise the output is HIGH for all other combinations of the input variables.

NOR Gate has a very useful property which makes it unique and important among all other Gates. The Boolean expression of any complexity can be implemented using NOR Gate only that is NOR Gate alone can be employed to realize all possible Boolean expressions without the need of any other Gate. This property of NOR Gate is called Functional Completeness, due to this property the entire microprocessor can be designed using NOR Gate only! NOR Gate shares this property with NAND Gate and both of the Gates are called Universal Gates.

Now let us understand the circuit that implements the NOR Gate. NOR Gate can be implemented in a variety of ways depending upon the electronic components used to design the circuit. For example diodes, transistors, resistors and combination of these components can implement the NOR Gate. The most popular techniques for designing the NOR gates are TTL (Transistor-Transistor Logic) and CMOS (Complementary Metal Oxide Semiconductor Transistor) logics. An example of the basic circuit implementing the NOR Gate functionality is shown in the figure below:

The inputs A and B of the NOR Gate are connected at the base of the transistors T1 and T2 respectively and the output is taken from the collector. The transistor here acts as the switch so when the signal is applied at the base of the transistor the transistor starts conducting and shorts the output to the ground similarly when no signal is applied at the input the output is connected to the Vcc as shown. When signal is applied neither at input A nor B none of the transistors T1 and T2 turn on and the output terminal remains connected to the Vcc and thus output of the NOR Gate remains HIGH. When signal is applied either at input A or B corresponding transistor T1 or T2 turns on and shorts the output terminal to the ground thus output of the NOR Gate gets LOW. Similar is the case when signal is applied at both terminals. This how the transistors and resistors can be used to implement the NOR Gate functionality.

NOR gates are available in the IC packages. As mentioned earlier that TTL (Transistor-Transistor Logic) and CMOS (Complementary Metal Oxide Semiconductor) technologies are used to design NOR gate. One of the most popular IC for NOR Gate is 4001 which is a QUAD two inputs NOR Gate IC which means that this IC contains four independent two input NOR Gates. The pinout and connection diagram of the 4001 IC is shown below:

I hope this article will be helpful for. In the next article I will come up with other important topics. Till then stay connected, keep reading and enjoy learning.

The post Introduction to NOR Gate appeared first on projectiot123 Technology Information Website worldwide.

]]>The post Introduction to NAND Gate appeared first on projectiot123 Technology Information Website worldwide.

]]>- AND Gate.
- OR Gate.
- NOT Gate.

AND Gate implements the Boolean AND function, OR gate implements the Boolean OR function and likewise NOT Gate (also called Inverter) implements the Boolean NOT function. The Boolean expressions of each basic gate along with their schematics symbol are shown in the following figure.

**Introduction to NAND Gate**

The input and output variables of the Boolean function can assume any one of two possible values called ‘0’ or ‘1’. In terms of positive logic ‘0’ is considered to be low and ‘1’ is considered to be HIGH, whereas in terms of the negative logic ‘0’ is considered to be HIGH and ‘1’ is considered to be LOW. Any Boolean expression can be implemented using these three basic logic Gates.

These basic digital logic gates that is AND, OR and NOT gates can be combined together in particular topologies to realize other important gates. The most common examples are NAND and NOR Gate. NAND Gate is formed by the combination of AND and NOT Gate in series that is by connecting the output of the AND at the input of the NOT Gate similarly NOR Gate is formed by the combination of OR and NOT Gate. Other important Gates formed by the combination of basic logic gates are XOR (Exclusive OR) and XNOR (Exclusive NOR) Gates. Here the discussion is oriented to the NAND Gate only.

**NAND Gate:**

As pointed out in previous paragraph that NAND Gate is the combination of AND and NOT Gate with input of NOT Gate connected at the output of the AND Gate. Thus corresponding to each combination of the inputs NAND Gate will have an output that is the complement of the output of the AND Gate. The schematic symbol along with the basic circuit of the NAND Gate is as shown in the following image:

As shown in the image above NAND Gate process the inputs A and B in such a way that first AND Gate manipulates the input variables A and B to generate A.B and then NOT gate acts on A.B to generate complement of the A.B. The Bubble symbol at the AND gate represents the negation of the output of the AND Gate.

**NAND Gate Truth Table:**

The relation between the state of the output variable and that of the input variables is represented in the form of the table. This table is called the Truth Table. The Truth Table of the NAND Gate along with its schematics symbol is shown below:

The output of the NAND Gate is LOW if and only if both of its inputs are HIGH otherwise its output is HIGH, note that the output of the NAND Gate is exact complement of the AND Gate in which output will be HIGH if only if inputs are HIGH otherwise the output is LOW for all other combinations of the input variables.

**Universality of NAND Gate:**

NAND Gate has a very useful property which makes it unique and important among all other Gates. The Boolean expression of any complexity can be implemented using NAND Gate only that NAND Gate alone can be employed to realize all possible Boolean expressions without the need of any other Gate. This property of NAND Gate is called Functional Completeness, due to this property the entire microprocessor can be designed using NAND Gate only! NAND Gate shares this property with NOR Gate and both of the Gates are called Universal Gates.

**NAND Gate Circuit:**

Now let us understand the circuit that implements the NAND Gate. NAND Gate can be implemented in a variety of ways depending upon the electronic components used to design the circuit. For example diodes, transistors, resistors and combination of these components can implement the NAND Gate. The most popular techniques for designing the NAND gates are TTL (Transistor-Transistor Logic) and CMOS (Complementary Metal Oxide Semiconductor Transistor) logics. An example of the basic circuit implementing the NAND Gate functionality is shown in the figure below:

The inputs A and B of the NAND Gate are connected at the base of the transistors T1 and T2 respectively and the output is taken from the collector. The transistor here acts as the switch so when the signal is applied at the base of the transistor the transistor starts conducting and shorts the output to the ground similarly when no voltage is applied at the input the output is connected to the Vcc as shown. When signal is applied at input A only the transistor T1 turns ON and transistor T2 remains off thus the output terminal is connected to the Vcc and output of the NAND Gate is HIGH, similar is the case when signal is applied at input B only. When no signal is applied at either A and B the output terminal is still connected to the Vcc and output remains HIGH. But when signal is applied at both inputs A and B both transistors T1 and T2 turns on and shorts the output terminal to ground thus output will get LOW this is how the circuit implements the NAND Gate functionality.

NAND gates are available in the IC packages. As mentioned earlier that TTL (Transistor-Transistor Logic) and CMOS (Complementary Metal Oxide Semiconductor) technologies are used to design NAND gate. One of the most popular IC for NAND Gate is 4011 which is a QUAD two inputs NAND Gate IC which means that this IC contains four independent two input NAND Gates. The pinout and connection diagram of the 7404 IC is shown below:

I hope this article will be helpful for. In the next article I will other important topics. Till then stay connected, keep reading and enjoy learning.

The post Introduction to NAND Gate appeared first on projectiot123 Technology Information Website worldwide.

]]>The post Introduction to OR Gate appeared first on projectiot123 Technology Information Website worldwide.

]]>Digital logic gates are the building blocks of the digital circuit. Each basic logic gate implements a unique Boolean function and a complex Boolean expression is implemented using the network of basic gates. Three basic logic gates are:

- AND Gate.
- OR Gate.
- NOR Gate.

OR Gate implements the OR Boolean function and similarly AND and NOR Gates implements the OR and NOR functions respectively. Here the discussion will be oriented around the OR Gate only.

OR Gate is one of the basic logic gates that implement the logical OR operation. The Boolean expression that represents the logical conjunction and thus represents the functionality of the OR Gate is as shown below:

As shown OR Gate function is represented by the plus sign. OR Gate operates on minimum two inputs and depending upon the state of each input it delivers the output which is governed by the Boolean OR function. In Boolean algebra each variable can have one of the two values that is ‘0’ or ‘1’. Thus in the Boolean expression of the OR Gate the inputs A and B can assume either ‘0’ or ‘1’ and C which is the output of the OR function of input A and input B also assumes either ‘0’ or ‘1’.

The relation between the state of the output and that of the inputs is represented in the form of the table. This table is called the Truth Table. The Truth Table of the OR Gate along with its schematics symbol is shown below:

In order for the output to be HIGH one of the inputs A or B should be HIGH, the output is also HIGH when both A and B are HIGH otherwise the output would be LOW as represented by the truth table. In terms of Positive Logic ‘1’ is considered to be ‘HIGH’ and ‘0’ is considered as ‘LOW’ and in terms of Negative Logic ‘1’ is considered as ‘LOW’ and ‘0’ is considered to be ‘HIGH’.

Now let us understand the circuit that implements the OR Gate. OR Gate can be implemented in a variety of ways depending upon the electronic components used to design the circuit. For example diodes, transistors, resistors and combination of these components can implement the OR Gate. The most popular techniques for designing the OR gates are TTL (Transistor-Transistor Logic) and CMOS (Complementary Metal Oxide Semiconductor Transistor) logics. An example of the circuit implementing the OR Gate is shown in the figure below:

The inputs of the OR Gate are connected to base of the transistors and the output is connected to the emitter. As shown in the figure when either of the inputs A and B is HIGH the output is also HIGH or if one of the inputs is HIGH the output is HIGH as well. Here transistor acts as the switch when both or one of the transistors are on the voltage will appear at the emitter. It is important to note here that 5V represents the logic HIGH and 0 V represents the logic LOW.

OR gates are available in the IC packages. One of the most popular IC for OR Gate is 4071 which is a Quad-two input OR Gate IC which means that this IC contains 4 independent two input OR Gates. The pinout and connection diagram of the 4071 IC is shown below:

That is all for now I hope this article would be helpful for you in the next article I will come up with NOT gate. Stay connected, keep reading and enjoy learning.

The post Introduction to OR Gate appeared first on projectiot123 Technology Information Website worldwide.

]]>The post Introduction to NOT Gate appeared first on projectiot123 Technology Information Website worldwide.

]]>Digital logic gates are the building blocks of the digital circuit. Each basic logic gate implements a unique Boolean function and a complex Boolean expression is implemented using the network of basic gates. Three basic logic gates are:

- AND Gate.
- OR Gate.
- NOR Gate.

NOT Gate implements the NOT Boolean function and similarly AND and OR Gates implements the AND and OR functions respectively. Here the discussion will be oriented around the NOT Gate only.

NOT Gate is one of the basic logic gates that implement the logical NOT operation. NOT Gate is single-input single-output Gate and commonly referred as Inverter as it inverts its input; the output of the NOT Gate is complement of its input. The operation of the NOT Gate is simplest among all basic gates. The Boolean expression that represents the logical conjunction and thus represents the functionality of the NOT Gate is as shown below:

The NOT function is represented by the ‘BAR’ sign as shown above. The BAR represents that the output of the NOT Gate will be the complement / inverse of its input. As in the case of AND and OR Gate the input of the NOT Gate is the Binary Variable which means that it can assume one of the two value that ‘0’ or ‘1’. Similarly the output will be either ‘0’ or ‘1’ depending on the input. If the input of the NOT Gate is ‘HIGH’ the output will be ‘LOW’ and vice versa.

The relation between the state of the output and that of the inputs is represented in the form of the table. This table is called the Truth Table. The Truth Table of the NOT Gate along with its schematics symbol is shown below:

As shown in the truth table when the input of the NOT Gate is LOW its output is HIGH and similarly when the input of the NOT Gate is HIGH the output will be LOW. In terms of Positive Logic ‘1’ is considered to be ‘HIGH’ and ‘0’ is considered as ‘LOW’ and in terms of Negative Logic ‘1’ is considered as ‘LOW’ and ‘0’ is considered to be ‘HIGH’. The bubble at the output of the NOT Gate represents the logical inversion.

Now let us understand the circuit that implements the NOT Gate. NOT Gate can be implemented in a variety of ways depending upon the electronic components used to design the circuit. For example diodes, transistors, resistors and combination of these components can implement the NOT Gate. The most popular techniques for designing the NOT gates are TTL (Transistor-Transistor Logic) and CMOS (Complementary Metal Oxide Semiconductor Transistor) logics. An example of the circuit implementing the NOT Gate is shown in the figure below:

The input of the NOT Gate is connected at the base of the transistor and the output is taken from the collector. The transistor here acts as the switch so when the voltage is applied at the base of the transistor the transistor starts conducting and shorts the output to the ground similarly when no voltage is applied at the input the output is connected to the Vcc as shown thus in this way the circuit implements the NOT function.

NOT gates are available in the IC packages. One of the most popular IC for NOT Gate is 7404 which is a HEX-single input NOT Gate IC which means that this IC contains 6 independent NOT Gates. The pinout and connection diagram of the 7404 IC is shown below:

That is all for now I hope this article would be helpful for you in the next article I will come up with XOR gate. Stay connected, keep reading and enjoy learning.

The post Introduction to NOT Gate appeared first on projectiot123 Technology Information Website worldwide.

]]>The post Introduction to AND Gate appeared first on projectiot123 Technology Information Website worldwide.

]]>

Digital logic gates are the building blocks of the digital circuit. Each basic logic gate implements a unique Boolean function and a complex Boolean expression is implemented using the network of basic gates. Three basic logic gates are:

- AND Gate.
- OR Gate.
- NOR Gate.

AND Gate implements the AND Boolean function and similarly OR and NOR Gates implements the OR and NOR functions respectively. Here the discussion will be oriented around the AND Gate only.

AND Gate is one of the basic logic gates that implement the logical conjunction operation. The Boolean expression that represents the logical conjunction and thus represents the functionality of the AND Gate is as shown below:

As shown AND Gate function is represented by the dot. AND Gate operates on minimum two inputs and depending upon the state of each input it delivers the output which is governed by the Boolean AND function. In Boolean algebra each variable can have one of the two values that is ‘0’ or ‘1’. Thus in the Boolean expression of the AND Gate the inputs A and B can assume either ‘0’ or ‘1’ and C which is the output of the AND function of input A and input B also assumes either ‘0’ or ‘1’.

The relation between the state of the output and that of the input is represented in the form of the table. This table is called the Truth Table. The Truth Table of the AND Gate along with its schematics symbol is shown below:

In order for the output to be HIGH both inputs A and B should be HIGH otherwise the output would be LOW. In terms of Positive Logic ‘1’ is considered to be ‘HIGH’ and ‘0’ is considered as ‘LOW’ and in terms of Negative Logic ‘1’ is considered as ‘LOW’ and ‘0’ is considered to be ‘HIGH’.

Now let us understand the circuit that implements the AND Gate. AND Gate can be implemented in a variety of ways depending upon the electronic components required to design the circuit. For example diodes, transistors, resistors and combination of these components can implement the AND Gate. The most popular techniques for designing the AND gates are TTL (Transistor-Transistor Logic) and CMOS (Complementary Metal Oxide Semiconductor Transistor) logics. An example of the circuit implementing the AND Gate is shown in the figure below:

The inputs of the AND Gate are connected to base of the transistors and the output is connected to the emitter. As shown in the figure when both of inputs A and B are HIGH the output is also HIGH. Here transistor acts as the switch when both of the transistors are on the voltage will appear at the emitter. It is important to note here that 5V represents the logic HIGH and 0 V represents the logic LOW.

AND gates are available in the IC packages. One of the most popular IC for AND Gate is 7408 which is a Quad-two input AND Gate IC which means that this IC contains 4 independent two input AND Gates. The pinout and connection diagram of the 7408 IC is shown below:

That is all for now I hope this article would be helpful for you in the next article I will come up with OR gate. Stay connected, keep reading and enjoy learning.

The post Introduction to AND Gate appeared first on projectiot123 Technology Information Website worldwide.

]]>The post Proteus Download and Install appeared first on projectiot123 Technology Information Website worldwide.

]]>After reading this post the reader will be able to learn how to Download and Install Proteus software, its applications, functionality and hardware of the Proteus Software. So sit back, keep reading and enjoy learning.

in this post i will tell you how to Download Proteus and install Proteus Software. there are many versions of Proteus.

we have a** Arduino Library for Proteus **

The post Proteus Download and Install appeared first on projectiot123 Technology Information Website worldwide.

]]>The post AUTOMATIC TOLL PLAZA SYSTEM appeared first on projectiot123 Technology Information Website worldwide.

]]>In this final year electronics project **Automatic toll plaza system using PIC microcontroller **we introduce the new system about toll plaza system. In this our country daily has many people death due to the traffic problem. We used in this system emergency exit for Ambulance automatic open the barrier due to the siren of Ambulance by using voice detection module.

** **In this final year electronics project **Automatic toll plaza system using PIC microcontroller **first of all we give the supply voltage to the circuit. In this project Automatic toll plaza system using PIC microcontroller we use for normal vehicles and ambulance. For normal vehicle we use IR sensor to detect the coin. When enter the coin then barrier is open and car. When ambulance is come then sound detector module detect the siren of ambulance and automatic open the barrier for ambulance. All the process of input and output execute by PIC microcontroller according programming. We also use in this final year electronics project **Automatic toll plaza system using PIC microcontroller** LCD for display the status show of system and also used a DC gear motor for barrier open and close and driver of motor to operate the motor.

The post AUTOMATIC TOLL PLAZA SYSTEM appeared first on projectiot123 Technology Information Website worldwide.

]]>