This document provides an overview of logic families. It discusses different logic families including TTL, IIL, ECL, NMOS, and CMOS. It covers characteristics of logic gates such as fan-in, fan-out, noise margin, propagation delay, and input and output characteristics. It also discusses diodes, BJTs, and MOSFETs as switching elements. The document compares various logic families in terms of packing density, power consumption, and gate delay. Additionally, it covers topics such as open collector output, interfacing between logic families, and tri-state logic.
Multiplexers and demultiplexers allow digital information from multiple sources to be routed through a single line. A multiplexer has multiple data inputs, select lines to choose an input, and a single output. A demultiplexer has a single input, select lines to choose an output, and multiple outputs. Bigger multiplexers and demultiplexers can be built by cascading smaller ones. Multiplexers can implement logic functions by using the select lines as variables and routing the input lines to the output.
TTL and CMOS are the two main logic families. TTL uses bipolar transistors and was previously dominant, while CMOS now dominates due to its lower power consumption. TTL provides high speed but uses more power, while CMOS is slower but more power efficient. Both have evolved over time with different sub-families for various applications.
A multiplexer (MUX) is a digital switch that selects one of several input lines and outputs the selected input to a single output line. It uses select lines to determine which input is connected to the output. A typical application is connecting multiple audio/video sources like an MP3 player, laptop, satellite receiver, or cable TV to a single output destination like a home theater system. The document demonstrates a 4-to-1 MUX that uses two select lines A and B to choose one of four data inputs D0, D1, D2, or D3 and output it to line Y.
This document discusses different logic families including Resistor Transistor Logic (RTL), Diode Transistor Logic (DTL), Transistor-Transistor Logic (TTL), and Emitter Coupled Logic (ECL). It provides circuit diagrams and explanations of the working principles for each logic family. Key characteristics like fan-in, fan-out, propagation delay, noise immunity, and power dissipation are compared for each logic family.
A demultiplexer is a device that takes a signal containing multiple data streams and reconstructs the original separate streams. It works in reverse of a multiplexer, which combines multiple streams into one signal. Demultiplexers come in various types depending on the number of select lines, which determine how many output streams they can separate the combined signal into, from 1-to-2 up to 1-to-16. Common applications of demultiplexers include communication systems and converting serial to parallel signals.
This document discusses latches and flip flops, which are types of sequential logic circuits. It describes the basic components and functioning of latches like SR latches, D latches, and gated latches. For flip flops, it covers SR flip flops, D flip flops, JK flip flops, and master-slave flip flops. The key differences between latches and flip flops are that latches do not have a clock input while flip flops are edge-triggered by a clock signal. Latches and flip flops are used as basic storage elements in more complex sequential circuits and in computer components like registers and RAM.
This document provides an overview of different digital logic families. It begins by introducing logic gates and integrated circuits. It then classifies logic families as either bipolar or unipolar, and lists examples of each. Key specifications of digital ICs are defined, including propagation delay, fan-in/fan-out, input/output logic levels, and noise margin. Transistor-transistor logic (TTL) and complementary metal-oxide-semiconductor (CMOS) circuits are described. The TTL NAND gate uses multiple emitter transistors while the CMOS NAND gate uses both P-channel and N-channel MOSFETs. Emitter-coupled logic (ECL) provides the fastest
The document contains a list of 23 microprocessor lab programs and 6 interfacing programs for an electronics and communication course. The programs cover topics like data transfer, arithmetic operations, sorting, prime number generation, string operations, matrix multiplication and more. The document provides contents, program descriptions and assembly language code for some of the programs.
Multiplexers and demultiplexers allow digital information from multiple sources to be routed through a single line. A multiplexer has multiple data inputs, select lines to choose an input, and a single output. A demultiplexer has a single input, select lines to choose an output, and multiple outputs. Bigger multiplexers and demultiplexers can be built by cascading smaller ones. Multiplexers can implement logic functions by using the select lines as variables and routing the input lines to the output.
TTL and CMOS are the two main logic families. TTL uses bipolar transistors and was previously dominant, while CMOS now dominates due to its lower power consumption. TTL provides high speed but uses more power, while CMOS is slower but more power efficient. Both have evolved over time with different sub-families for various applications.
A multiplexer (MUX) is a digital switch that selects one of several input lines and outputs the selected input to a single output line. It uses select lines to determine which input is connected to the output. A typical application is connecting multiple audio/video sources like an MP3 player, laptop, satellite receiver, or cable TV to a single output destination like a home theater system. The document demonstrates a 4-to-1 MUX that uses two select lines A and B to choose one of four data inputs D0, D1, D2, or D3 and output it to line Y.
This document discusses different logic families including Resistor Transistor Logic (RTL), Diode Transistor Logic (DTL), Transistor-Transistor Logic (TTL), and Emitter Coupled Logic (ECL). It provides circuit diagrams and explanations of the working principles for each logic family. Key characteristics like fan-in, fan-out, propagation delay, noise immunity, and power dissipation are compared for each logic family.
A demultiplexer is a device that takes a signal containing multiple data streams and reconstructs the original separate streams. It works in reverse of a multiplexer, which combines multiple streams into one signal. Demultiplexers come in various types depending on the number of select lines, which determine how many output streams they can separate the combined signal into, from 1-to-2 up to 1-to-16. Common applications of demultiplexers include communication systems and converting serial to parallel signals.
This document discusses latches and flip flops, which are types of sequential logic circuits. It describes the basic components and functioning of latches like SR latches, D latches, and gated latches. For flip flops, it covers SR flip flops, D flip flops, JK flip flops, and master-slave flip flops. The key differences between latches and flip flops are that latches do not have a clock input while flip flops are edge-triggered by a clock signal. Latches and flip flops are used as basic storage elements in more complex sequential circuits and in computer components like registers and RAM.
This document provides an overview of different digital logic families. It begins by introducing logic gates and integrated circuits. It then classifies logic families as either bipolar or unipolar, and lists examples of each. Key specifications of digital ICs are defined, including propagation delay, fan-in/fan-out, input/output logic levels, and noise margin. Transistor-transistor logic (TTL) and complementary metal-oxide-semiconductor (CMOS) circuits are described. The TTL NAND gate uses multiple emitter transistors while the CMOS NAND gate uses both P-channel and N-channel MOSFETs. Emitter-coupled logic (ECL) provides the fastest
The document contains a list of 23 microprocessor lab programs and 6 interfacing programs for an electronics and communication course. The programs cover topics like data transfer, arithmetic operations, sorting, prime number generation, string operations, matrix multiplication and more. The document provides contents, program descriptions and assembly language code for some of the programs.
This document summarizes key concepts about combinational logic circuits. It defines combinational logic as circuits whose outputs depend only on the current inputs, in contrast to sequential logic which also depends on prior inputs. Common combinational circuits are described like half and full adders used for arithmetic, as well as decoders. The design process for combinational circuits is outlined involving specification, formulation, optimization and technology mapping. Implementation of functions using NAND and NOR gates is also discussed.
Encoders convert decimal input to binary coded decimal (BCD) output, while decoders convert BCD input to decimal output displayed on a 7-segment display. An example encoder converts decimal numbers to their BCD coded form, while an example decoder converts BCD codes into the decimal numbers they represent, which are then shown on a 7-segment LED display. The document provides examples of encodings and decoding between decimal, BCD, and 7-segment display representations and tests the reader with questions about decoding BCD inputs.
- A half adder adds two 1-bit binary numbers and produces a sum and carry output. It uses one XOR and one AND gate. The full adder adds three 1-bit binary numbers (two inputs and a carry input) and produces a sum and carry output. It is made up of two half adders joined by an OR gate.
- The key difference between a half adder and full adder is that a full adder has a third input for the carry input from the previous addition, while a half adder only has two inputs and is used as a basic building block for full adders. A full adder allows adding multi-bit binary numbers by chaining full adders together and
The document discusses programming timers and counters in the 8051 microcontroller. It describes the two timers/counters in the 8051, timer 0 and timer 1. It explains how to use the timers as timers or counters through settings in the TMOD register. The basic registers for the timers like TH0, TL0, TH1, TL1 are described. Programming examples are provided to illustrate how to set the timer values, start and stop the timers, and generate delays.
power point presentation regarding the number system conversions, representation of negative numbers and various codes of representations and error detection and correction codes.
This document discusses programmable logic devices (PLDs). It describes the different types of PLDs including SPLDs, CPLDs, and FPGAs. SPLDs are the least complex, while CPLDs have higher capacity than SPLDs and allow for more complex logic circuits. FPGAs have the greatest logic capacity and consist of an array of configurable logic blocks and programmable interconnects. The document also covers how PLDs are programmed using schematic entry or text-based entry along with required programming software and hardware.
This document discusses sequential circuits and their analysis. It defines sequential logic as circuits whose outputs depend not only on current inputs but also past inputs, requiring some type of memory. There are two types of sequential circuits: synchronous use a clock for synchronization, while asynchronous can change output at any time. Analysis of sequential circuits involves obtaining a description of the input-output-state sequence over time using techniques like logic diagrams, state tables, characteristic tables, and state diagrams. Various flip-flop designs are presented, including the SR latch, D latch using transmission gates, and master-slave flip-flop. Timing considerations like clock period and setup time are also covered.
A combinational circuit is a logic circuit whose output is solely determined by the present input. It has no internal memory and its output depends only on the current inputs. A half adder is a basic combinational circuit that adds two single bits and produces a sum and carry output. A full adder adds three bits and produces a sum and carry like the half adder. Other combinational circuits discussed include half and full subtractors, decoders, encoders, and priority encoders.
In digital electronics, a decoder can take the form of a multiple-input, multiple-output logic circuit that converts coded inputs into coded outputs, where the input and output codes are different e.g. n-to-2n , binary-coded decimal decoders. Decoding is necessary in applications such as data multiplexing, 7 segment display and memory address decoding.
An encoder is a device, circuit, transducer, software program, algorithm or person that converts information from one format or code to another. The purpose of encoder is standardization, speed, secrecy, security, or saving space by shrinking size. Encoders are combinational logic circuits and they are exactly opposite of decoders. They accept one or more inputs and generate a multibit output code.
This document discusses different types of flip-flops including edge-triggered flip-flops like the S-R, D, and J-K flip-flops. It describes their characteristics such as how their output changes depending on the input and clock signal. The S-R flip-flop can be set or reset. The D flip-flop copies its input to the output on the clock edge. The J-K flip-flop can toggle its output. The T flip-flop is a single-input version of the J-K flip-flop that toggles its output. Flip-flops have applications in data transfer and frequency division.
The BINARY to GRAY CODE CONVERTER is a digital circuit that is used to convert the binary input into the corresponding equivalent gray code at its output
This document discusses multiplexers and demultiplexers. It defines them as devices that allow digital information from several sources to be routed onto a single line (multiplexers) or distributed to multiple output lines (demultiplexers). The key properties of multiplexers and demultiplexers are described, including the relationship between the number of inputs, outputs, and selection lines. Examples of implementing multiplexers and demultiplexers using logic gates are provided.
A multiplexer has multiple inputs and a single output line, using select lines to determine which input is connected to the output. It is used to increase the amount of data that can be sent over a network. A demultiplexer is the reverse, with one input and multiple output lines, using select lines to send a signal to one of the output lines. Both are used in communication systems, computer memory, and other applications to efficiently transmit data or connect parts of a system.
Sequential circuits consist of combinational logic and memory elements like latches and flip-flops. There are different types of latches and flip-flops that differ in their trigger mechanisms and outputs, including SR latches, D latches, and edge-triggered flip-flops like SR, D, and JK flip-flops. Asynchronous inputs can directly set or reset flip-flop outputs independent of the clock signal.
This document provides an introduction to PIC microcontrollers. It discusses the architecture of PIC microcontrollers, including the 16C6x and 16C7x architectures. It describes the registers, memory, and instruction set of PIC microcontrollers. Some key points covered include the Harvard architecture, pipelining, addressing modes, arithmetic, logical, and conditional instructions. Peripherals like timers and interrupts are also mentioned.
This document provides information about filters and transmission lines. It discusses different types of filters including low pass, high pass, band pass, and band stop filters. It describes the ideal characteristics of filters and discusses ladder networks used to create filters. Constant K-filters are described along with derivations of equations for phase shift, attenuation, cutoff frequencies, and component values for low pass, high pass, and band pass constant K-filters. A band stop constant K-filter configuration is also shown.
In these slides the concept of BCD or Decimal Adder have explained in detail with the add of animations so that user may understand the concept easily. at the end the demonstration has also made to understand the working of BCD adder in a better way.
This document introduces information theory and channel capacity models. It discusses several channel models including the binary symmetric channel (BSC), binary erasure channel, and additive white Gaussian noise channel. It explains how channel capacity is defined as the maximum rate of error-free transmission and derives the capacity for some basic channels. The document also covers channel coding techniques like interleaving that can improve performance by converting burst errors into random errors.
Logic gates are elementary building blocks of digital circuits that have inputs and outputs representing binary digits 0 and 1. There are several basic types of logic gates including AND, OR, NOT, XOR, NAND, NOR, and XNOR gates. Each gate functions according to specific rules - for example, an AND gate only outputs 1 if all its inputs are 1, while a NAND gate produces the opposite output of an AND gate. Logic gates are used in various electronic devices and circuits.
This document discusses different types of digital logic families. It describes Transistor-Transistor Logic (TTL) circuits, including TTL NAND gates which use a totem pole configuration to provide high speed and low output impedance. Metal-oxide-semiconductor (MOS) and complementary MOS (CMOS) circuits are also covered, with CMOS NAND gates using both N-channel and P-channel MOSFETs for low power dissipation. Emitter-coupled logic (ECL) is described as the fastest logic family using current-mode switching, though it has higher power dissipation. Key specifications for digital ICs like propagation delay, power, noise immunity, and fan-in
This document provides an overview of different logic families, including their classification, characteristics, and examples. The key points covered are:
- Logic families represent different digital circuit methodologies and include RTL, DTL, TTL, ECL, and CMOS.
- Characteristics compared include fan-in, fan-out, noise margin, propagation delay, and whether the family uses bipolar or MOSFET transistors.
- Examples of basic gates are provided for each family, such as the NOR gate for RTL and the NAND gate for DTL. Differences in speed and power consumption between families are also noted.
This document summarizes key concepts about combinational logic circuits. It defines combinational logic as circuits whose outputs depend only on the current inputs, in contrast to sequential logic which also depends on prior inputs. Common combinational circuits are described like half and full adders used for arithmetic, as well as decoders. The design process for combinational circuits is outlined involving specification, formulation, optimization and technology mapping. Implementation of functions using NAND and NOR gates is also discussed.
Encoders convert decimal input to binary coded decimal (BCD) output, while decoders convert BCD input to decimal output displayed on a 7-segment display. An example encoder converts decimal numbers to their BCD coded form, while an example decoder converts BCD codes into the decimal numbers they represent, which are then shown on a 7-segment LED display. The document provides examples of encodings and decoding between decimal, BCD, and 7-segment display representations and tests the reader with questions about decoding BCD inputs.
- A half adder adds two 1-bit binary numbers and produces a sum and carry output. It uses one XOR and one AND gate. The full adder adds three 1-bit binary numbers (two inputs and a carry input) and produces a sum and carry output. It is made up of two half adders joined by an OR gate.
- The key difference between a half adder and full adder is that a full adder has a third input for the carry input from the previous addition, while a half adder only has two inputs and is used as a basic building block for full adders. A full adder allows adding multi-bit binary numbers by chaining full adders together and
The document discusses programming timers and counters in the 8051 microcontroller. It describes the two timers/counters in the 8051, timer 0 and timer 1. It explains how to use the timers as timers or counters through settings in the TMOD register. The basic registers for the timers like TH0, TL0, TH1, TL1 are described. Programming examples are provided to illustrate how to set the timer values, start and stop the timers, and generate delays.
power point presentation regarding the number system conversions, representation of negative numbers and various codes of representations and error detection and correction codes.
This document discusses programmable logic devices (PLDs). It describes the different types of PLDs including SPLDs, CPLDs, and FPGAs. SPLDs are the least complex, while CPLDs have higher capacity than SPLDs and allow for more complex logic circuits. FPGAs have the greatest logic capacity and consist of an array of configurable logic blocks and programmable interconnects. The document also covers how PLDs are programmed using schematic entry or text-based entry along with required programming software and hardware.
This document discusses sequential circuits and their analysis. It defines sequential logic as circuits whose outputs depend not only on current inputs but also past inputs, requiring some type of memory. There are two types of sequential circuits: synchronous use a clock for synchronization, while asynchronous can change output at any time. Analysis of sequential circuits involves obtaining a description of the input-output-state sequence over time using techniques like logic diagrams, state tables, characteristic tables, and state diagrams. Various flip-flop designs are presented, including the SR latch, D latch using transmission gates, and master-slave flip-flop. Timing considerations like clock period and setup time are also covered.
A combinational circuit is a logic circuit whose output is solely determined by the present input. It has no internal memory and its output depends only on the current inputs. A half adder is a basic combinational circuit that adds two single bits and produces a sum and carry output. A full adder adds three bits and produces a sum and carry like the half adder. Other combinational circuits discussed include half and full subtractors, decoders, encoders, and priority encoders.
In digital electronics, a decoder can take the form of a multiple-input, multiple-output logic circuit that converts coded inputs into coded outputs, where the input and output codes are different e.g. n-to-2n , binary-coded decimal decoders. Decoding is necessary in applications such as data multiplexing, 7 segment display and memory address decoding.
An encoder is a device, circuit, transducer, software program, algorithm or person that converts information from one format or code to another. The purpose of encoder is standardization, speed, secrecy, security, or saving space by shrinking size. Encoders are combinational logic circuits and they are exactly opposite of decoders. They accept one or more inputs and generate a multibit output code.
This document discusses different types of flip-flops including edge-triggered flip-flops like the S-R, D, and J-K flip-flops. It describes their characteristics such as how their output changes depending on the input and clock signal. The S-R flip-flop can be set or reset. The D flip-flop copies its input to the output on the clock edge. The J-K flip-flop can toggle its output. The T flip-flop is a single-input version of the J-K flip-flop that toggles its output. Flip-flops have applications in data transfer and frequency division.
The BINARY to GRAY CODE CONVERTER is a digital circuit that is used to convert the binary input into the corresponding equivalent gray code at its output
This document discusses multiplexers and demultiplexers. It defines them as devices that allow digital information from several sources to be routed onto a single line (multiplexers) or distributed to multiple output lines (demultiplexers). The key properties of multiplexers and demultiplexers are described, including the relationship between the number of inputs, outputs, and selection lines. Examples of implementing multiplexers and demultiplexers using logic gates are provided.
A multiplexer has multiple inputs and a single output line, using select lines to determine which input is connected to the output. It is used to increase the amount of data that can be sent over a network. A demultiplexer is the reverse, with one input and multiple output lines, using select lines to send a signal to one of the output lines. Both are used in communication systems, computer memory, and other applications to efficiently transmit data or connect parts of a system.
Sequential circuits consist of combinational logic and memory elements like latches and flip-flops. There are different types of latches and flip-flops that differ in their trigger mechanisms and outputs, including SR latches, D latches, and edge-triggered flip-flops like SR, D, and JK flip-flops. Asynchronous inputs can directly set or reset flip-flop outputs independent of the clock signal.
This document provides an introduction to PIC microcontrollers. It discusses the architecture of PIC microcontrollers, including the 16C6x and 16C7x architectures. It describes the registers, memory, and instruction set of PIC microcontrollers. Some key points covered include the Harvard architecture, pipelining, addressing modes, arithmetic, logical, and conditional instructions. Peripherals like timers and interrupts are also mentioned.
This document provides information about filters and transmission lines. It discusses different types of filters including low pass, high pass, band pass, and band stop filters. It describes the ideal characteristics of filters and discusses ladder networks used to create filters. Constant K-filters are described along with derivations of equations for phase shift, attenuation, cutoff frequencies, and component values for low pass, high pass, and band pass constant K-filters. A band stop constant K-filter configuration is also shown.
In these slides the concept of BCD or Decimal Adder have explained in detail with the add of animations so that user may understand the concept easily. at the end the demonstration has also made to understand the working of BCD adder in a better way.
This document introduces information theory and channel capacity models. It discusses several channel models including the binary symmetric channel (BSC), binary erasure channel, and additive white Gaussian noise channel. It explains how channel capacity is defined as the maximum rate of error-free transmission and derives the capacity for some basic channels. The document also covers channel coding techniques like interleaving that can improve performance by converting burst errors into random errors.
Logic gates are elementary building blocks of digital circuits that have inputs and outputs representing binary digits 0 and 1. There are several basic types of logic gates including AND, OR, NOT, XOR, NAND, NOR, and XNOR gates. Each gate functions according to specific rules - for example, an AND gate only outputs 1 if all its inputs are 1, while a NAND gate produces the opposite output of an AND gate. Logic gates are used in various electronic devices and circuits.
This document discusses different types of digital logic families. It describes Transistor-Transistor Logic (TTL) circuits, including TTL NAND gates which use a totem pole configuration to provide high speed and low output impedance. Metal-oxide-semiconductor (MOS) and complementary MOS (CMOS) circuits are also covered, with CMOS NAND gates using both N-channel and P-channel MOSFETs for low power dissipation. Emitter-coupled logic (ECL) is described as the fastest logic family using current-mode switching, though it has higher power dissipation. Key specifications for digital ICs like propagation delay, power, noise immunity, and fan-in
This document provides an overview of different logic families, including their classification, characteristics, and examples. The key points covered are:
- Logic families represent different digital circuit methodologies and include RTL, DTL, TTL, ECL, and CMOS.
- Characteristics compared include fan-in, fan-out, noise margin, propagation delay, and whether the family uses bipolar or MOSFET transistors.
- Examples of basic gates are provided for each family, such as the NOR gate for RTL and the NAND gate for DTL. Differences in speed and power consumption between families are also noted.
This document provides an overview of different logic families used in digital circuits. It discusses Resistor Transistor Logic (RTL), Diode Transistor Logic (DTL), Transistor-Transistor Logic (TTL), Emitter Coupled Logic (ECL) and Complementary Metal-Oxide-Semiconductor (CMOS) logic families. It describes the basic components, operation and advantages/limitations of each logic family type. The document is intended as lecture notes for a course on logic families used in digital electronics.
This document provides an overview of different logic families used in digital circuits. It discusses the classification of logic families into bipolar and unipolar families. It describes key characteristics of different logic families like RTL, DTL, TTL, ECL and CMOS. RTL uses resistors and transistors, DTL added diodes for improved fan-out. TTL replaced diodes with transistors for higher speed. ECL uses differential amplifiers to prevent saturation for highest speeds. CMOS combines high speed with low power consumption. Fan-in, fan-out, noise margin and propagation delay are also explained for different logic families.
This document discusses different types of digital integrated circuits (ICs) including logic families. It describes transistor logic families like resistor-transistor logic (RTL), resistor-capacitor transistor logic (RCTL), diode-transistor logic (DTL), high threshold logic (HTL), and transistor-transistor logic (TTL). It also discusses metal-oxide semiconductor (MOS) logic families like PMOS, NMOS, and complementary MOS (CMOS) as well as bipolar logic families like emitter-coupled logic (ECL). The document explains the characteristics and workings of these different logic families.
This document discusses different logic families, including their characteristics, circuits, and workings. It covers Resistor Transistor Logic (RTL), which was not available in monolithic form and uses a NOR gate. It also discusses Diode Transistor Logic (DTL), which was the first commercial available IC logic family and uses a NAND gate. Finally, it covers Transistor Transistor Logic (TTL), the most popular logic family, which uses a NAND gate with a TOTEMPOL output stage for increased speed and output current capability.
Transistors have different operational modes including active, cut-off, and saturation. The cut-off mode refers to the state when the transistor is turned off and does not allow current to flow. It acts as an open switch. The saturation mode is when the transistor is fully on, allowing maximum current flow with minimal voltage drop, effectively acting as a closed switch. Understanding the different transistor modes is important for their application in electronic circuits for tasks like amplification and switching.
This document discusses different digital logic families and characteristics. It describes Resistor-Transistor Logic (RTL) which consists of resistors and transistors, with the emitters connected to ground and collectors tied through a resistor. Transistor-Transistor Logic (TTL) is also discussed, which depends solely on transistors. TTL uses multiple emitter transistors for inputs and a totem-pole output for high speed and low impedance. The document provides details on RTL and TTL gate operations.
Emitter Coupled Logic (ECL) was invented in 1956 and used transistors operating in an unsaturated mode. ECL uses current switching where the input voltage controls the current flowing through transistor legs. When the input voltage is low or high, one transistor is cut off while the other is active, starving the cut off transistor. ECL provides very fast operation of less than 1 nanosecond but has high power consumption and low noise immunity.
This document discusses digital logic concepts including binary logic, logic gates, logic families, and programmable logic devices. It defines binary logic as consisting of binary variables and logical operations. It states that the three basic logic gates are AND, OR, and NOT. It also discusses combinational logic circuits, including half adders, full adders, decoders, encoders, multiplexers and comparators. Finally, it covers programmable logic devices such as ROM, PROM, EPROM and EEPROM.
Digital logic families classify integrated circuits by their circuit technology. A logic family consists of chips that perform logic functions like AND and OR with similar input/output characteristics. Popular families include TTL, ECL, MOS, and CMOS. CMOS uses fewer transistors than other families for inversion and is known for low power. Logic levels and noise margins define input and output voltage thresholds. Transition times and capacitive loading affect a circuit's propagation delay.
1) The remote controller for a robot contains 4 relays in the upper part, with each relay having 5 pins including normally closed, normally open, and common pins. An IC is used to provide high or low output to switches and convert low current to high current.
2) The lower part of the remote contains an IC connected to the 4 switches. Each switch has its own resistor to resist high current flow.
3) Wires from the relay common parts connect to the robot motor. Relays and ICs protect components from high voltages when relays switch off. ICs integrate transistors, diodes, resistors and capacitors on a semiconductor substrate. Digital ICs contain logic gates while analog ICs
The document discusses CMOS inverters, which are logic gates made from complementary pairs of PMOS and NMOS transistors. It describes the basic structure and working of a CMOS inverter, including that it consumes low static power, has high noise immunity, and its output switches between 0V and the supply voltage VDD. The document also covers characteristics such as propagation delay, rise/fall times, and advantages like low power consumption. CMOS inverters are widely used in integrated circuits due to their efficient switching and robust noise performance.
Transistors were invented in 1947 and have three terminals - emitter, base, and collector. They come in two types, NPN and PNP, and work by amplifying or switching signals. There are different transistor structures and types including BJT, FET, and HBT. Transistors operate in three regions - cutoff, saturation, and active. Load line analysis involves plotting the output characteristics to determine collector current based on collector-emitter voltage.
Presentation on various logic families like RTL, DTL, TTL, IIL etc with diagram, advantages and limitations plus some basic concepts like fan out, noise margin, propagation delay.
Digital logic gates called NAND and NOR are considered universal logic gates because all other logic gates can be constructed using only NAND gates or only NOR gates. Transistor-Transistor Logic (TTL) is one of the most widely used integrated circuit logic families. TTL uses a multi-emitter input transistor and a totem-pole output stage to provide a variable output resistance and achieve high noise immunity. Key parameters for logic families include input/output voltage levels, propagation delay, power dissipation, and noise margins.
Cloud Computing (Infrastructure as a Service)UNIT 2SURBHI SAROHA
This document provides an overview of Infrastructure as a Service (IaaS) cloud computing models. It defines IaaS and describes its key characteristics. It then discusses the three main IaaS deployment models - private cloud, public cloud, and hybrid cloud. For each model, it outlines their definition, examples, advantages and disadvantages. Finally, it lists several important aspects to consider when managing a hybrid cloud environment, such as integration, security, resource optimization, and automation.
Management Information System(Unit 2).pptxSURBHI SAROHA
This document provides an overview of management information systems (MIS) planning. It discusses the concepts of organizational planning, the planning process, and computational support for planning. It then describes the characteristics of the control process and the nature of control in an organization. Specifically, it outlines the steps in MIS planning, including defining outcomes, forming a team, defining system requirements, finding the right solution, selecting vendors, estimating costs, creating an implementation plan, and understanding risks. It also discusses setting performance standards, measuring actual performance, comparing to standards, analyzing deviations, and taking corrective action as part of the basic control process.
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This document summarizes a lecture on searching techniques, including linear search and binary search. It describes how linear search sequentially checks each item in a list to find a match, having time complexity of O(n) in average and worst cases. Binary search uses a divide and conquer approach, comparing the middle element of a sorted list to determine if the target is in the upper or lower half, narrowing the search space and having time complexity of O(log n). The advantages and drawbacks of each method are also outlined.
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This document provides an overview of management information systems (MIS). It begins with an introduction to information systems in business and their typical components, including hardware, software, data, and telecommunications. It then discusses the fundamentals of information systems and defines the major types of information systems, including transaction processing systems, office automation systems, knowledge work systems, management information systems, decision support systems, and executive support systems. The document also distinguishes MIS from data processing and outlines some key characteristics of MIS.
Introduction to Cloud Computing(UNIT 1).pptxSURBHI SAROHA
This document provides an introduction to cloud computing, including definitions, characteristics, service models, deployment models, and virtualization concepts. It defines cloud computing as storing and accessing data and programs on remote servers hosted on the internet. The main service models are infrastructure as a service (IaaS), platform as a service (PaaS), and software as a service (SaaS). The primary deployment models are public cloud, private cloud, hybrid cloud, community cloud, and multi-cloud. Virtualization allows for the sharing of physical resources and is key to cloud computing.
The document provides an overview of key topics in Java including event handling, the delegation event model, event classes, listener interfaces, adapter and inner classes, working with windows, graphics and text, AWT controls, layout managers, menus, Java applets, beans, and servlets. It discusses event types, how events are handled in Java using the delegation model with sources and listeners, common event classes and interfaces, and how to draw graphics and text. It also covers using various AWT components, different layout managers, creating menus, and basics of applets, beans, and servlets.
This document discusses various concepts related to file organization and data warehousing. It defines key terms like file, record, fixed and variable length records. It describes different types of single-level and multi-level indexes used for file organization, including B-trees. It also provides an overview of data warehousing concepts such as architecture and operations. The benefits of data warehousing for business analytics and insights are highlighted. Different file organization methods like sequential, heap, hash and indexed sequential access are also summarized.
This document provides an overview of transaction processing and recovery in database management systems. It discusses topics like transaction processing, concurrency control techniques including locking and timestamping protocols, recovery from transaction failures using log-based recovery, and checkpoints. The key aspects covered are the ACID properties of transactions, serialization testing using precedence graphs, recoverable schedules, and concurrency control methods like locking, timestamp ordering, and validation-based protocols.
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Object-Oriented Programming with Java UNIT 1SURBHI SAROHA
This document provides an introduction and syllabus for an Object-Oriented Programming with Java course. The syllabus covers key Java concepts like keywords, variables, data types, operators, decision making, classes, objects, methods, inheritance, and arrays. It also describes the importance and features of Java, including being platform independent, secure, portable, robust, and high performance. The document includes code examples for a first Java program and demonstrates various operators.
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- The three schema architecture separating the conceptual, internal, and external schemas.
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Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...Dr. Vinod Kumar Kanvaria
Exploiting Artificial Intelligence for Empowering Researchers and Faculty,
International FDP on Fundamentals of Research in Social Sciences
at Integral University, Lucknow, 06.06.2024
By Dr. Vinod Kumar Kanvaria
Thinking of getting a dog? Be aware that breeds like Pit Bulls, Rottweilers, and German Shepherds can be loyal and dangerous. Proper training and socialization are crucial to preventing aggressive behaviors. Ensure safety by understanding their needs and always supervising interactions. Stay safe, and enjoy your furry friends!
A workshop hosted by the South African Journal of Science aimed at postgraduate students and early career researchers with little or no experience in writing and publishing journal articles.
This presentation includes basic of PCOS their pathology and treatment and also Ayurveda correlation of PCOS and Ayurvedic line of treatment mentioned in classics.
বাংলাদেশের অর্থনৈতিক সমীক্ষা ২০২৪ [Bangladesh Economic Review 2024 Bangla.pdf] কম্পিউটার , ট্যাব ও স্মার্ট ফোন ভার্সন সহ সম্পূর্ণ বাংলা ই-বুক বা pdf বই " সুচিপত্র ...বুকমার্ক মেনু 🔖 ও হাইপার লিংক মেনু 📝👆 যুক্ত ..
আমাদের সবার জন্য খুব খুব গুরুত্বপূর্ণ একটি বই ..বিসিএস, ব্যাংক, ইউনিভার্সিটি ভর্তি ও যে কোন প্রতিযোগিতা মূলক পরীক্ষার জন্য এর খুব ইম্পরট্যান্ট একটি বিষয় ...তাছাড়া বাংলাদেশের সাম্প্রতিক যে কোন ডাটা বা তথ্য এই বইতে পাবেন ...
তাই একজন নাগরিক হিসাবে এই তথ্য গুলো আপনার জানা প্রয়োজন ...।
বিসিএস ও ব্যাংক এর লিখিত পরীক্ষা ...+এছাড়া মাধ্যমিক ও উচ্চমাধ্যমিকের স্টুডেন্টদের জন্য অনেক কাজে আসবে ...
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...PECB
Denis is a dynamic and results-driven Chief Information Officer (CIO) with a distinguished career spanning information systems analysis and technical project management. With a proven track record of spearheading the design and delivery of cutting-edge Information Management solutions, he has consistently elevated business operations, streamlined reporting functions, and maximized process efficiency.
Certified as an ISO/IEC 27001: Information Security Management Systems (ISMS) Lead Implementer, Data Protection Officer, and Cyber Risks Analyst, Denis brings a heightened focus on data security, privacy, and cyber resilience to every endeavor.
His expertise extends across a diverse spectrum of reporting, database, and web development applications, underpinned by an exceptional grasp of data storage and virtualization technologies. His proficiency in application testing, database administration, and data cleansing ensures seamless execution of complex projects.
What sets Denis apart is his comprehensive understanding of Business and Systems Analysis technologies, honed through involvement in all phases of the Software Development Lifecycle (SDLC). From meticulous requirements gathering to precise analysis, innovative design, rigorous development, thorough testing, and successful implementation, he has consistently delivered exceptional results.
Throughout his career, he has taken on multifaceted roles, from leading technical project management teams to owning solutions that drive operational excellence. His conscientious and proactive approach is unwavering, whether he is working independently or collaboratively within a team. His ability to connect with colleagues on a personal level underscores his commitment to fostering a harmonious and productive workplace environment.
Date: May 29, 2024
Tags: Information Security, ISO/IEC 27001, ISO/IEC 42001, Artificial Intelligence, GDPR
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A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
How to Manage Your Lost Opportunities in Odoo 17 CRMCeline George
Odoo 17 CRM allows us to track why we lose sales opportunities with "Lost Reasons." This helps analyze our sales process and identify areas for improvement. Here's how to configure lost reasons in Odoo 17 CRM
2. SYLLABUS
Diode
BJT & MOS as switching element.
Concept of transfer characteristics.
Input characteristic and output characteristics of logic gates.
Fan- in
Fan-out
Noise margin
Circuit concept and comparison of various logic families : TTL,IIL,ECL,NMOS,CMOS
Tri-state logic
3. SYLLABUS
Open collector output
Interfacing between logic families
Packing density
Power consumption & gate delay.
4. Diode
The anode which is the positive terminal of a diode is represented with A and
the cathode, which is the negative terminal is represented with K.
To know the anode and cathode of a practical diode, a fine line is drawn on the
diode which means cathode, while the other end represents anode.
5. Diode(Cont….)
Diodes are used to protect circuits by limiting the voltage and to also transform
AC into DC.
Semiconductors like silicon and germanium are used to make the most of the
diodes.
Even though they transmit current in a single direction, the way with which they
transmit differs.
There are different kinds of diodes and each type has its own applications.
6. BJT & MOS as switching element
Bipolar junction transistors (Also known as BJTs) can be used as an amplifier,
filter, rectifier, oscillator, or even a switch, which we cover an example in the
first section.
The transistor will operate as an amplifier or other linear circuit if the transistor is
biased into the linear region.
The transistor can be used as a switch if biased in the saturation and cut-off
regions.
This allows current to flow (or not) in other parts of a circuit.
Because a transistor’s collector current is proportionally limited by its base current,
it can be used as a sort of current-controlled switch.
7. BJT & MOS as switching element(Cont..)
A relatively small flow of electrons sent through the base of the transistor has the
ability to exert control over a much larger flow of electrons through the collector.
Bipolar junction transistor (BJT) has three terminals and two junctions.
The function of the transistor is to amplify the signal.
The three terminals of BJT are base, emitter and collector.
BJT is either a PNP transistor or NPN transistor based on the doping type of the
three terminals.
Using the transistor as a switch is the simplest application of transistors.
8. How does a BJT act as a switch?
A transistor has three modes: active region, cut off region and the saturation
region.
The transistor acts as a switch in the cut-off mode and the saturation mode.
The transistor is fully off in the cutoff region and fully on the saturation region.
A transistor can also be used as a switch since a small electric current flowing
through one part of it can cause larger current flow through the other part of the
transistor.
9. MOS as a Switch
MOSFETs exhibit three regions of operation viz., Cut-off, Linear or Ohmic and
Saturation.
Among these, when MOSFETs are to be used as amplifiers, they are required to be
operated in their ohmic region wherein the current through the device increases with
an increase in the applied voltage.
On the other hand, when the MOSFETs are required to function as switches, they
should be biased in such a way that they alter between cut-off and saturation states.
This is because, in cut-off region, there is no current flow through the device while in
saturation region there will be a constant amount of current flowing through the
device, just mimicking the behaviour of an open and closed switch, respectively.
This functionality of MOSFETs is exploited in many electronic circuits as they offer
higher switching rates when compared to BJTs (bipolar junction transistors).
10. MOS(Cont….)
The MOSFET (Metal Oxide Semiconductor Field Effect Transistor) transistor is a
semiconductor device that is widely used for switching purposes and for the
amplification of electronic signals in electronic devices.
A MOSFET is either a core or integrated circuit where it is designed and
fabricated in a single chip because the device is available in very small sizes.
In general, The body of the MOSFET is in connection with the source terminal
thus forming a three-terminal device such as a field-effect transistor.
MOSFET is generally considered as a transistor and employed in both the
analog and digital circuits.
11. A MOSFET is a four-terminal device having source(S), gate (G), drain (D) and body
(B) terminals.
12. Concept of transfer characteristics
The transfer characteristics of a system is defined to be the pseudo-static
relationship between the input and output variable.
If the system is a voltage-in, voltage-out system we would term this pseudo-static
relationship the dc transfer characteristics.
A system with an input XIN and an output XOUT .
In electrical systems the input and output quantities, typically termed signals, are
often dependent on a single additional input variable, time.
In this case the input and output signals would time-dependent voltages or
currents.
13. Input characteristic and output
characteristics of logic gates
Propagation delay
It is the time interval between the application of the input pulse and the
occurrence of the output. It is an important characteristic of the digital logic
family. If the propagation delay is less, then the speed at which the IC operates
will be faster.
Let THL is the propagation delay when the output changes from logic 0 to 1 and
TLH is the delay when the output changes from logic 1 to 0. The maximum value of
THL and TLH is considered as the propagation delay for that logic gate.
14. Fan in and Fan out
Fan-in refers to the number of inputs in a digital logic gate family. For the
example given in the figure below, the EX-OR gate has three inputs. So fan-in
for the given EX-OR gate is 3.
15. Fan-out
Fan-out refers to the number of inputs that is driven by the output of another
logic gates. For example, the following circuit has an EX-OR gate, which drives 4
NOT gates. So fan-out of EX-OR gate is 4.
16. Fan-out
•The maximum number of digital input that the output of a single logic gate can
feed and the gate must be same logic family.
• Fan Out is calculated from the amount of current available in the output of a
gate and the amount of current needed in each input of the connecting gate.
•It is specified by manufacturer and is provided in the data sheet.
•Exceeding the specified maximum load may cause a malfunction because the
circuit will not be able supply the demanded power.
17. What is Noise?
It is an unwanted signal that is superimposed on the normal operating signal.
Noise may be due to various factors like operating environment, radiations, stray
electrical and magnetic fields.
In digital logic circuits, the binary values 0 and 1 represent the LOW and HIGH
voltage levels. Due to the interference of the noises, the voltage levels may
increase or decrease. This may lead to the wrong operation of the device.
The noise immunity is the ability of the logic device to tolerate the noise without
causing spurious change to the output voltage. Noise margin allows the logic
device to function properly within the specified limits.
18. Noise Margin
•Noise is present in all real systems.
This adds random fluctuations to voltages representing logic levels.
•Hence, the voltage ranges defining the logic levels are more tightly constrained
at the output of a gate than at the input.
• Small amounts of noise will not affect the circuit.
The maximum noise voltage that can be tolerated by a circuit is termed its noise
immunity (noise Margin).
20. Circuit concept and comparison of various
logic families : TTL,IIL,ECL,NMOS,CMOS
Tri-state logic
21.
22. Resistor Transistor Logic(RTL)
The basic RTL device is a NOR gate.
The inputs represent either logic level HIGH (1) or LOW (0).
The logic level LOW is the voltage that drives corresponding transistor in cut-off
region, while logic level HIGH drives it into saturation region.
If both the inputs are LOW, then both the transistors are in cut-off i.e. they are
turned-off. Thus, voltage Vcc appears at output I.e. HIGH.
If either transistor or both of them are applied HIGH input, the voltage Vcc drops
across Rc and output is LOW.
23. Diode Transistor Logic
The diode-transistor logic, also termed as DTL, replaced RTL family because of greater
fan-out capability and more noise margin.
DTL circuits mainly consists of diodes and transistors that comprises DTL devices.
The basic DTL device is a NAND gate.
Two inputs to the gate are applied through diodes viz. D1, D2 .
The diode will conduct only when corresponding input is LOW.
If any of the diode is conducting i.e. when at least one input is LOW, the voltage at
output keeps transistor T in cut-off and subsequently, output of transistor is HIGH.
If all inputs are HIGH, all diodes are non-conducting, transistor T is in saturation, and its
output is LOW.
24. Diode Transistor Logic
Due to number of diodes used in this circuit, the speed of the circuit is
significantly low.
Hence this family of logic gates is modified to transistor-transistor logic i.e. TTL
family which has been discussed on next slide.
25. Transistor Transistor Logic
TTL family is a modification to the DTL.
It has come to existence so as to overcome the speed limitations of DTL family.
The basic gate of this family is TTL NAND gate.
Q3 is cutoff (act like a high RC ) when output transistor Q4 is saturated and Q3 is
saturated (act like a low RC ) when output transistor Q4 is cutoff .
Thus one transistor is ON at one time.
The combination of Q3 and Q4 is called TOTEM POLE arrangement.
Q1 is called input transistor, which is multi emitter transistor, that drive transistor Q2
which is used to control Q3 and Q4.
Diode D1 and D2 are used to protect Q1 from unwanted negative voltages and diode
D3 ensures when Q4 is ON, Q3 is OFF.
26. Transistor Transistor Logic
The output impedance is asymmetrical between the high and low state, making
them unsuitable for driving transmission lines.
This drawback is usually overcome by buffering the outputs with special line-
driver devices where signals need to be sent through cables.
ECL, by virtue of its symmetric low-impedance output structure, does not have this
drawback.
27.
28. Complimentary MOS (CMOS)
Considerably lower energy consumption than TTL and ECL, which has made
portable electronics possible.
Most widely used family for large-scale devices
Combines high speed with low power consumption
Usually operates from a single supply of 5 – 15 V
Excellent noise immunity of about 30% of supply voltage
Can be connected to a large number of gates (about 50) .
30. The “Tri-state Buffer”
A Tri-state Buffer can be thought of as an input controlled switch with an output
that can be electronically turned “ON” or “OFF” by means of an external
“Control” or “Enable” ( EN ) signal input.
This control signal can be either a logic “0” or a logic “1” type signal resulting in
the Tri-state Buffer being in one state allowing its output to operate normally
producing the required output or in another state were its output is blocked or
disconnected.
Then a tri-state buffer requires two inputs.
One being the data input and the other being the enable or control input as
shown.
32. Open collector output
An open collector output refers to an output that is connected to the collector of
a transistor.
Basically, just think of a transistor. A BJT transistor has a base, a collector, and an
emitter.
An open collector output is an output device that is attached to an open collector
of a transistor.
By open collector, we mean a collector that is unattached to anything. It's just
open.
In order for an open collector output device to work, the open collector has to
receive sufficient power.
34. Interfacing between logic families
IC digital logic families
DL (Diode- logic)
DTL (Diode-transistor logic)
RTL (Resistor-transistor logic)
TTL (Transistor -transistor logic)
ECL (Emitter-coupled logic)
MOS (Metal-oxide semiconductor)
CMOS (Complementary Metal-oxide semiconductor)
35. Voltage-Related Interfacing Problems
In some interfacing situations, a HIGH output pin may produce a voltage that is
too low to be recognized as a HIGH by the input pin it’s connected to.
The solution in such cases is to use a pull-up resistor
Example: TTL to CMOS
A TTL HIGH output may be as low as 2.4 V.
But a CMOS input expects HIGHs to be at least 3.33 V.
37. Packing density
TTL is Saturated Logic, ECL is Maximum power consumption, NMOS is Highest
packing density, CMOS is Least power consumption.
38. Power consumption & gate delay
Propagation delay of a gate is not the same thing as rise or fall time for an
individual transistor.
To propagate through an IC a signal may have to pass through several transistors
and may pass through different transistor paths depending on the kind of input
(data, select, enable, etc) being asserted.
A small amount of delay in signal transmission is unavoidable because of the finite
speed of light, which travels one foot per nanosecond (signals move in wire at
nearly the speed of light).
But most delay in switching circuits is due to the time it takes charges stored in
one place to move to another.
39. Power consumption & gate delay(Cont…)
The removal of stored charge from a capacitor through a resistance to "ground"
takes time, in the same way that emptying a bathtub through the drain takes time.
Electronic switches are made of transistors.
Consider the input side of a common-emitter transistor circuit, and the case of
turning it off-charge caught in the base region must be removed before the flow
of current from collector to emitter is stopped.
To a certain approximation the base-emitter junction of a transistor acts like a
capacitor.