Designs are likely to experience many different environmental changes, marketing requirement changes and user abuse; choosing a device that is flexible, programmable, and upgradeable is necessary. Without question, the most flexible, programmable and upgradeable device on the market is the Programmable System on a Chip (PSoC). PSoC is a mixed-signal array which includes analog and digital resources as well as an integrated microcontroller all on the same chip!
CapSense Capacitive Sensors Sigma Delta AlgorithmRuth Moore
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Cypress' CapSense Sigma-Delta algorithm (CSD) uses switched capacitor circuitry and analog/digital components to convert changes in capacitance from a sensor electrode into a digital bit stream. The bit stream is analyzed to determine if a conductive object is present by measuring the change in counts over measurement windows. CSD modulates the sensor capacitance using a switched capacitor network and comparator to create a variable duty cycle bit stream. This enables low power capacitive sensing for touch interfaces.
This document analyzes the total harmonic distortion (THD) of 7, 9, and 11 level cascaded H-bridge multilevel inverters using multicarrier pulse width modulation. The analysis found that THD in the output voltage decreases and output voltage increases with more levels. Simulations in MATLAB/Simulink showed that an 11-level inverter had the lowest THD at 11.1%, while a 7-level inverter had the highest THD at 24.64%. More levels therefore better reduced the harmonic distortion.
This document defines various terms used in electrical engineering and related fields. It provides definitions for terms such as ABCD parameters, ABCD matrix, ABCD formalism, abnormal event, abort, absolute sensitivity, and others. Each definition is brief, typically one sentence or less.
An Explicit Approach for Dynamic Power Evaluation for Deep submicron Global I...IDES Editor
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As the VLSI process technology is shrinking to the
nanometer regime, power consumption of on-chip VLSI
interconnects has become a crucial and an important issue.
There are several methodologies proposed to estimate the onchip
power consumption using Voltage Mode Signaling
technique (VMS). But the major drawback of VMS is that it
increases the power consumption of on-chip interconnects
compared to current mode signaling (CMS). A closed form
formula is, thus, necessary for current mode signaling to
accurately estimate the power dissipation in the distributed
line. In this paper, we derived an explicit dynamic power
formula in S-domain based on Modified Nodal Analysis
(MNA) formulation. The usefulness of our approach is that
dynamic power consumption of an interconnect line can be
estimated accurately and efficiently at any operating
frequency. By substituting s=0 in the vector of node voltages
in our model results similar solution as that of Bashirullah
et. al. Comparison of simulation results with other
established models justifies the accuracy of our approach.
Hvdc Transmission Jntu Model Paper{Www.Studentyogi.Com}guest3f9c6b
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This document contains four sample exam papers for an HVDC Transmission course. Each paper contains 8 questions and students must answer 5 questions. The questions cover various topics related to HVDC transmission systems including: voltage selection methods; Graetz circuit operation; rectifier and inverter characteristics; power controllers; mathematical modeling; fault protection; harmonic elimination; and filter types and design.
The document describes a modified Dickson charge pump design that reduces power consumption during input clock transitions. A PMOS transistor is added in series with each capacitor stage to increase the time constant, slowing the charge transfer. This reduces power from 340.5uW to 28.85uW at no load for the Dickson versus modified design. Output voltages are similar but slightly lower for the modified design. At 10MOhm and 40MOhm loads, power savings during transitions are also realized compared to the standard Dickson design while maintaining comparable output voltages. In conclusion, the modified design successfully reduces transition power consumption without significantly impacting output voltage.
IJERD (www.ijerd.com) International Journal of Engineering Research and Devel...IJERD Editor
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The document presents a hybrid pulse width modulation (HPWM) method for voltage source inverter (VSI) fed induction motor drives. It proposes a generalized PWM (GPWM) algorithm that varies a constant to generate different discontinuous PWM (DPWM) algorithms along with the space vector PWM (SVPWM) algorithm. The GPWM approach uses instantaneous phase voltages to calculate inverter gating times, reducing complexity compared to the classical SVPWM approach. Simulation results show that SVPWM gives better performance at low modulation indices, while DPWM is better at higher indices. Therefore, the paper presents a HPWM algorithm to achieve superior waveform quality across all modulation indices.
CapSense Capacitive Sensors Sigma Delta AlgorithmRuth Moore
Â
Cypress' CapSense Sigma-Delta algorithm (CSD) uses switched capacitor circuitry and analog/digital components to convert changes in capacitance from a sensor electrode into a digital bit stream. The bit stream is analyzed to determine if a conductive object is present by measuring the change in counts over measurement windows. CSD modulates the sensor capacitance using a switched capacitor network and comparator to create a variable duty cycle bit stream. This enables low power capacitive sensing for touch interfaces.
This document analyzes the total harmonic distortion (THD) of 7, 9, and 11 level cascaded H-bridge multilevel inverters using multicarrier pulse width modulation. The analysis found that THD in the output voltage decreases and output voltage increases with more levels. Simulations in MATLAB/Simulink showed that an 11-level inverter had the lowest THD at 11.1%, while a 7-level inverter had the highest THD at 24.64%. More levels therefore better reduced the harmonic distortion.
This document defines various terms used in electrical engineering and related fields. It provides definitions for terms such as ABCD parameters, ABCD matrix, ABCD formalism, abnormal event, abort, absolute sensitivity, and others. Each definition is brief, typically one sentence or less.
An Explicit Approach for Dynamic Power Evaluation for Deep submicron Global I...IDES Editor
Â
As the VLSI process technology is shrinking to the
nanometer regime, power consumption of on-chip VLSI
interconnects has become a crucial and an important issue.
There are several methodologies proposed to estimate the onchip
power consumption using Voltage Mode Signaling
technique (VMS). But the major drawback of VMS is that it
increases the power consumption of on-chip interconnects
compared to current mode signaling (CMS). A closed form
formula is, thus, necessary for current mode signaling to
accurately estimate the power dissipation in the distributed
line. In this paper, we derived an explicit dynamic power
formula in S-domain based on Modified Nodal Analysis
(MNA) formulation. The usefulness of our approach is that
dynamic power consumption of an interconnect line can be
estimated accurately and efficiently at any operating
frequency. By substituting s=0 in the vector of node voltages
in our model results similar solution as that of Bashirullah
et. al. Comparison of simulation results with other
established models justifies the accuracy of our approach.
Hvdc Transmission Jntu Model Paper{Www.Studentyogi.Com}guest3f9c6b
Â
This document contains four sample exam papers for an HVDC Transmission course. Each paper contains 8 questions and students must answer 5 questions. The questions cover various topics related to HVDC transmission systems including: voltage selection methods; Graetz circuit operation; rectifier and inverter characteristics; power controllers; mathematical modeling; fault protection; harmonic elimination; and filter types and design.
The document describes a modified Dickson charge pump design that reduces power consumption during input clock transitions. A PMOS transistor is added in series with each capacitor stage to increase the time constant, slowing the charge transfer. This reduces power from 340.5uW to 28.85uW at no load for the Dickson versus modified design. Output voltages are similar but slightly lower for the modified design. At 10MOhm and 40MOhm loads, power savings during transitions are also realized compared to the standard Dickson design while maintaining comparable output voltages. In conclusion, the modified design successfully reduces transition power consumption without significantly impacting output voltage.
IJERD (www.ijerd.com) International Journal of Engineering Research and Devel...IJERD Editor
Â
The document presents a hybrid pulse width modulation (HPWM) method for voltage source inverter (VSI) fed induction motor drives. It proposes a generalized PWM (GPWM) algorithm that varies a constant to generate different discontinuous PWM (DPWM) algorithms along with the space vector PWM (SVPWM) algorithm. The GPWM approach uses instantaneous phase voltages to calculate inverter gating times, reducing complexity compared to the classical SVPWM approach. Simulation results show that SVPWM gives better performance at low modulation indices, while DPWM is better at higher indices. Therefore, the paper presents a HPWM algorithm to achieve superior waveform quality across all modulation indices.
This document discusses capacitors in series and parallel circuits. It provides the objectives of understanding how to calculate the equivalent capacitance of capacitors connected in series and parallel. Formulas are given for calculating the total capacitance of series circuits as 1/CT = 1/C1 + 1/C2 + 1/C3 and of parallel circuits as CT = C1 + C2 + C3. Examples are included to demonstrate solving problems involving up to three capacitors in series or parallel using these formulas. Quizzes with solutions are also provided to help reinforce the concepts.
The document discusses the power-bandwidth tradeoff in MIMO systems. It begins with background on MIMO systems, including their structure and key performance improvements like spatial multiplexing gain and diversity gain. It then defines spectral efficiency and energy efficiency, noting that maximizing both is not possible due to the inherent tradeoff between them known as the EE-SE tradeoff. The concept of this tradeoff is explained through mathematical formulations. As an example, the EE-SE tradeoff for an AWGN channel is shown. Approximation methods for determining the EE-SE tradeoff in MIMO systems are also presented.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
This document describes a novel transimpedance amplifier with variable gain. It proposes a new topology using only three active devices and no passive components. Simulations show it achieves comparable noise, bandwidth, and input impedance as a conventional design using 30uW power. Its transimpedance gain can be varied from 68dB to 78dB by adjusting a control voltage, allowing for a 10dB range of programmability. The proposed design occupies less layout space and is well-suited for applications requiring many sensors.
Linear Ic Applications Jntu Model Paper{Www.Studentyogi.Com}guest3f9c6b
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This document contains questions from past exam papers for the subject "Linear IC Applications". It includes 8 questions related to topics like differential amplifiers, op-amps, filters, oscillators, timers, DACs, ADCs and multiplexers. Students are required to answer any 5 questions out of the 8 questions provided. The questions test the students' understanding of circuit analysis and design of various applications using linear integrated circuits.
This document discusses transmission line basics and concepts. It covers transmission line equivalent circuits, relevant equations for propagation and characteristic impedance, and examples of transmission line structures. It also discusses reflection coefficients and diagrams, and provides formulas for calculating per-unit length capacitance, inductance, impedance, and propagation delay of transmission lines. Special cases for reflection coefficients when a transmission line is terminated in its characteristic impedance, presents an open circuit, or is short circuited are also summarized.
Coupling Aware Explicit Delay Metric for On- Chip RLC Interconnect for Ramp i...IDES Editor
Â
Recent years have seen significant research in
finding closed form expressions for the delay of the RLC
interconnect which improves upon the Elmore delay
model. However, several of these formulae assume a step
excitation. But in practice, the input waveform does have
a non zero time of flight. There are few works reported so
far which do consider the ramp inputs but lacks in the
explicit nature which could work for a wide range of
possible input slews. Elmore delay has been widely used
as an analytical estimate of interconnect delays in the
performance-driven synthesis and layout of VLSI routing
topologies. However, for typical RLC interconnections
with ramp input, Elmore delay can deviate by up to 100%
or more than SPICE computed delay since it is
independent of rise time of the input ramp signal. We
develop a novel analytical delay model based on the first
and second moments of the interconnect transfer function
when the input is a ramp signal with finite rise/fall time.
Delay estimate using our first moment based analytical
model is within 4% of SPICE-computed delay, and model
based on first two moments is within 2.3% of SPICE,
across a wide range of interconnects parameter values.
Evaluation of our analytical model is several orders of
magnitude faster than simulation using SPICE. We also
discuss the possible extensions of our approach for
estimation of source-sink delays for an arbitrary
interconnects trees.
The document discusses electromagnetic waves and transmission lines. It defines that electromagnetic waves propagate in dielectric mediums and are produced by accelerating electric charges. It also describes that in transverse electromagnetic waves, the electric and magnetic fields are perpendicular to the direction of propagation. Additionally, it explains that transmission lines have distributed inductance, capacitance, resistance, and conductance per unit length which can be modeled as an equivalent circuit. The input impedance of a transmission line is dependent on the characteristic impedance and load impedance.
This document discusses different types of digital-to-analog converters (DACs), including parallel DACs, improved resolution parallel DACs, and serial DACs. It describes voltage scaling DACs which use a resistor ladder network and charge scaling DACs which use a capacitor array. It also examines integral nonlinearity (INL) and differential nonlinearity (DNL) for these DAC types and provides examples of calculating resolution based on component tolerances.
1. The document discusses transmission line theory and parameters. Key topics covered include:
- Telegrapher's equation and circuit model for transmission lines
- Wave propagation and characteristic impedance calculations
- Reflection coefficient and standing wave ratio definitions
- Comparisons of transmission line, circuit, and field theories
2. Specific transmission line types are analyzed, including planar lines, coaxial cables. Equations are given for calculating the capacitance, conductance, inductance, resistance, and characteristic impedance of these common line configurations.
3. Simulation and modeling techniques for transmission lines are briefly mentioned, such as the transmission line matrix method for modeling microstrip lines in antennas and circuits.
International Journal of Engineering Research and Development is an international premier peer reviewed open access engineering and technology journal promoting the discovery, innovation, advancement and dissemination of basic and transitional knowledge in engineering, technology and related disciplines.
We follow "Rigorous Publication" model - means that all articles appear on IJERD after full appraisal, effectiveness, legitimacy and reliability of research content. International Journal of Engineering Research and Development publishes papers online as well as provide hard copy of Journal to authors after publication of paper. It is intended to serve as a forum for researchers, practitioners and developers to exchange ideas and results for the advancement of Engineering & Technology.
This document compares two current controllers - hysteresis control and proportional-integral (PI) control - for a five-level cascaded H-bridge multilevel inverter. Hysteresis control provides excellent dynamic performance but variable switching frequency, while PI control with sinusoidal pulse width modulation provides fixed switching frequency and better harmonic performance. Simulation results show that PI control achieves lower total harmonic distortion than hysteresis control under different load conditions, though hysteresis control has faster response. PI control is thus better suited for applications requiring lower harmonic distortion.
Adaptive control of saturated induction motor with uncertain load torqueAyyarao T S L V
Â
1) The document reviews an adaptive control method for induction motors with uncertain load torque and magnetic saturation.
2) A nonlinear adaptive controller is designed using a field oriented control approach. The controller estimates the unknown time-varying load torque through online identification.
3) Once the load torque is identified, the control decouples regulating rotor speed and flux amplitude to improve efficiency without affecting speed regulation. Adaptation laws are developed to track the load torque and regulate the motor's speed and flux.
Zuken - Improve pcb quality and cost with concurrent power integrity analysis...Zuken
Â
This document discusses power integrity challenges in modern PCB design and introduces an EDA methodology for concurrent power integrity simulation throughout the PCB design process. It covers topics like IC switching current needs, power distribution system impedance behavior, decoupling capacitor placement considerations, and examples of using power integrity simulation to optimize PCB designs. The methodology aims to identify power integrity issues earlier to improve quality and reduce costs compared to traditional verification later in the design flow.
The document summarizes different types of microwave devices:
1) A lossless divider uses a simple T junction transmission line but offers no isolation between ports.
2) A resistive divider uses lossy components in a T junction to match all three ports for an equal power split but results in signal power loss.
3) A waveguide directional coupler directs power between waveguides in a controlled manner.
4) A quadrature hybrid combines two input signals to produce two output signals with a 90 degree phase difference between them.
This document provides a sample question paper for Class XII Physics with instructions and questions. It contains 5 sections (A-E) with a total of 26 multiple choice and numerical questions worth 70 marks. Section A has 5 one-mark questions, Section B has 5 two-mark questions, Section C has 12 three-mark questions, Section D has 1 four-mark question and Section E has 3 five-mark questions. The document also provides important physical constants and formulas required to solve the questions.
This document provides a sample question paper for Class XII Physics with instructions and questions. It contains 5 sections (A-E) with a total of 26 questions of varying marks. Section A contains 5 one-mark questions, Section B contains 5 two-mark questions, Section C contains 12 three-mark questions, Section D contains 1 four-mark question and Section E contains 3 five-mark questions. The document also provides physical constants and formulas that may be required to solve the questions.
This document discusses cascaded H-bridge multilevel inverters and their symmetrical and asymmetrical configurations. It begins by introducing two-level and multilevel inverters, noting that multilevel inverters are better suited for high power and voltage applications as they reduce harmonics. There are three main multilevel inverter topologies: neutral-point-clamped, flying capacitors, and cascaded H-bridges. The cascaded H-bridge topology connects H-bridge cells in series to generate stepped voltage waveforms. Symmetrical configurations use equal DC voltages for each cell, while asymmetrical configurations use unequal voltages, allowing more voltage levels with the same number of cells. The document presents simulations of
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
My name is Spenser K. I am associated with mechanicalengineeringassignmenthelp.com for the past 12 years and have been helping the mechanical engineering students with their Microelectromechanical Assignment. I have a Ph.D. in Mechatronics Engineering from RMIT University Australia.
This document provides instructions for experiments using a cathode ray oscilloscope (CRO). The first experiment introduces the basic functions and controls of a CRO. Students will learn to display waveforms and measure the dc voltage, peak-to-peak voltage, and frequency of signals. The second experiment describes how to use a CRO to measure dc and ac voltages. The third experiment explains how to measure the frequency of an unknown signal by adjusting the time base to display one cycle over two divisions and calculating from the period. The overall document provides step-by-step guidance for using a CRO to visualize and analyze electrical signals.
Successive Approximation Algorithm (CSA) is a new capacitive sensing algorithm for the CY8C20x34 PSoC(R) device family. CSA enables the implementation of an array of capacitive sensors through switched capacitor circuitry, an analog multiplexer and digital counting function.
This document discusses capacitors in series and parallel circuits. It provides the objectives of understanding how to calculate the equivalent capacitance of capacitors connected in series and parallel. Formulas are given for calculating the total capacitance of series circuits as 1/CT = 1/C1 + 1/C2 + 1/C3 and of parallel circuits as CT = C1 + C2 + C3. Examples are included to demonstrate solving problems involving up to three capacitors in series or parallel using these formulas. Quizzes with solutions are also provided to help reinforce the concepts.
The document discusses the power-bandwidth tradeoff in MIMO systems. It begins with background on MIMO systems, including their structure and key performance improvements like spatial multiplexing gain and diversity gain. It then defines spectral efficiency and energy efficiency, noting that maximizing both is not possible due to the inherent tradeoff between them known as the EE-SE tradeoff. The concept of this tradeoff is explained through mathematical formulations. As an example, the EE-SE tradeoff for an AWGN channel is shown. Approximation methods for determining the EE-SE tradeoff in MIMO systems are also presented.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
This document describes a novel transimpedance amplifier with variable gain. It proposes a new topology using only three active devices and no passive components. Simulations show it achieves comparable noise, bandwidth, and input impedance as a conventional design using 30uW power. Its transimpedance gain can be varied from 68dB to 78dB by adjusting a control voltage, allowing for a 10dB range of programmability. The proposed design occupies less layout space and is well-suited for applications requiring many sensors.
Linear Ic Applications Jntu Model Paper{Www.Studentyogi.Com}guest3f9c6b
Â
This document contains questions from past exam papers for the subject "Linear IC Applications". It includes 8 questions related to topics like differential amplifiers, op-amps, filters, oscillators, timers, DACs, ADCs and multiplexers. Students are required to answer any 5 questions out of the 8 questions provided. The questions test the students' understanding of circuit analysis and design of various applications using linear integrated circuits.
This document discusses transmission line basics and concepts. It covers transmission line equivalent circuits, relevant equations for propagation and characteristic impedance, and examples of transmission line structures. It also discusses reflection coefficients and diagrams, and provides formulas for calculating per-unit length capacitance, inductance, impedance, and propagation delay of transmission lines. Special cases for reflection coefficients when a transmission line is terminated in its characteristic impedance, presents an open circuit, or is short circuited are also summarized.
Coupling Aware Explicit Delay Metric for On- Chip RLC Interconnect for Ramp i...IDES Editor
Â
Recent years have seen significant research in
finding closed form expressions for the delay of the RLC
interconnect which improves upon the Elmore delay
model. However, several of these formulae assume a step
excitation. But in practice, the input waveform does have
a non zero time of flight. There are few works reported so
far which do consider the ramp inputs but lacks in the
explicit nature which could work for a wide range of
possible input slews. Elmore delay has been widely used
as an analytical estimate of interconnect delays in the
performance-driven synthesis and layout of VLSI routing
topologies. However, for typical RLC interconnections
with ramp input, Elmore delay can deviate by up to 100%
or more than SPICE computed delay since it is
independent of rise time of the input ramp signal. We
develop a novel analytical delay model based on the first
and second moments of the interconnect transfer function
when the input is a ramp signal with finite rise/fall time.
Delay estimate using our first moment based analytical
model is within 4% of SPICE-computed delay, and model
based on first two moments is within 2.3% of SPICE,
across a wide range of interconnects parameter values.
Evaluation of our analytical model is several orders of
magnitude faster than simulation using SPICE. We also
discuss the possible extensions of our approach for
estimation of source-sink delays for an arbitrary
interconnects trees.
The document discusses electromagnetic waves and transmission lines. It defines that electromagnetic waves propagate in dielectric mediums and are produced by accelerating electric charges. It also describes that in transverse electromagnetic waves, the electric and magnetic fields are perpendicular to the direction of propagation. Additionally, it explains that transmission lines have distributed inductance, capacitance, resistance, and conductance per unit length which can be modeled as an equivalent circuit. The input impedance of a transmission line is dependent on the characteristic impedance and load impedance.
This document discusses different types of digital-to-analog converters (DACs), including parallel DACs, improved resolution parallel DACs, and serial DACs. It describes voltage scaling DACs which use a resistor ladder network and charge scaling DACs which use a capacitor array. It also examines integral nonlinearity (INL) and differential nonlinearity (DNL) for these DAC types and provides examples of calculating resolution based on component tolerances.
1. The document discusses transmission line theory and parameters. Key topics covered include:
- Telegrapher's equation and circuit model for transmission lines
- Wave propagation and characteristic impedance calculations
- Reflection coefficient and standing wave ratio definitions
- Comparisons of transmission line, circuit, and field theories
2. Specific transmission line types are analyzed, including planar lines, coaxial cables. Equations are given for calculating the capacitance, conductance, inductance, resistance, and characteristic impedance of these common line configurations.
3. Simulation and modeling techniques for transmission lines are briefly mentioned, such as the transmission line matrix method for modeling microstrip lines in antennas and circuits.
International Journal of Engineering Research and Development is an international premier peer reviewed open access engineering and technology journal promoting the discovery, innovation, advancement and dissemination of basic and transitional knowledge in engineering, technology and related disciplines.
We follow "Rigorous Publication" model - means that all articles appear on IJERD after full appraisal, effectiveness, legitimacy and reliability of research content. International Journal of Engineering Research and Development publishes papers online as well as provide hard copy of Journal to authors after publication of paper. It is intended to serve as a forum for researchers, practitioners and developers to exchange ideas and results for the advancement of Engineering & Technology.
This document compares two current controllers - hysteresis control and proportional-integral (PI) control - for a five-level cascaded H-bridge multilevel inverter. Hysteresis control provides excellent dynamic performance but variable switching frequency, while PI control with sinusoidal pulse width modulation provides fixed switching frequency and better harmonic performance. Simulation results show that PI control achieves lower total harmonic distortion than hysteresis control under different load conditions, though hysteresis control has faster response. PI control is thus better suited for applications requiring lower harmonic distortion.
Adaptive control of saturated induction motor with uncertain load torqueAyyarao T S L V
Â
1) The document reviews an adaptive control method for induction motors with uncertain load torque and magnetic saturation.
2) A nonlinear adaptive controller is designed using a field oriented control approach. The controller estimates the unknown time-varying load torque through online identification.
3) Once the load torque is identified, the control decouples regulating rotor speed and flux amplitude to improve efficiency without affecting speed regulation. Adaptation laws are developed to track the load torque and regulate the motor's speed and flux.
Zuken - Improve pcb quality and cost with concurrent power integrity analysis...Zuken
Â
This document discusses power integrity challenges in modern PCB design and introduces an EDA methodology for concurrent power integrity simulation throughout the PCB design process. It covers topics like IC switching current needs, power distribution system impedance behavior, decoupling capacitor placement considerations, and examples of using power integrity simulation to optimize PCB designs. The methodology aims to identify power integrity issues earlier to improve quality and reduce costs compared to traditional verification later in the design flow.
The document summarizes different types of microwave devices:
1) A lossless divider uses a simple T junction transmission line but offers no isolation between ports.
2) A resistive divider uses lossy components in a T junction to match all three ports for an equal power split but results in signal power loss.
3) A waveguide directional coupler directs power between waveguides in a controlled manner.
4) A quadrature hybrid combines two input signals to produce two output signals with a 90 degree phase difference between them.
This document provides a sample question paper for Class XII Physics with instructions and questions. It contains 5 sections (A-E) with a total of 26 multiple choice and numerical questions worth 70 marks. Section A has 5 one-mark questions, Section B has 5 two-mark questions, Section C has 12 three-mark questions, Section D has 1 four-mark question and Section E has 3 five-mark questions. The document also provides important physical constants and formulas required to solve the questions.
This document provides a sample question paper for Class XII Physics with instructions and questions. It contains 5 sections (A-E) with a total of 26 questions of varying marks. Section A contains 5 one-mark questions, Section B contains 5 two-mark questions, Section C contains 12 three-mark questions, Section D contains 1 four-mark question and Section E contains 3 five-mark questions. The document also provides physical constants and formulas that may be required to solve the questions.
This document discusses cascaded H-bridge multilevel inverters and their symmetrical and asymmetrical configurations. It begins by introducing two-level and multilevel inverters, noting that multilevel inverters are better suited for high power and voltage applications as they reduce harmonics. There are three main multilevel inverter topologies: neutral-point-clamped, flying capacitors, and cascaded H-bridges. The cascaded H-bridge topology connects H-bridge cells in series to generate stepped voltage waveforms. Symmetrical configurations use equal DC voltages for each cell, while asymmetrical configurations use unequal voltages, allowing more voltage levels with the same number of cells. The document presents simulations of
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
My name is Spenser K. I am associated with mechanicalengineeringassignmenthelp.com for the past 12 years and have been helping the mechanical engineering students with their Microelectromechanical Assignment. I have a Ph.D. in Mechatronics Engineering from RMIT University Australia.
This document provides instructions for experiments using a cathode ray oscilloscope (CRO). The first experiment introduces the basic functions and controls of a CRO. Students will learn to display waveforms and measure the dc voltage, peak-to-peak voltage, and frequency of signals. The second experiment describes how to use a CRO to measure dc and ac voltages. The third experiment explains how to measure the frequency of an unknown signal by adjusting the time base to display one cycle over two divisions and calculating from the period. The overall document provides step-by-step guidance for using a CRO to visualize and analyze electrical signals.
Successive Approximation Algorithm (CSA) is a new capacitive sensing algorithm for the CY8C20x34 PSoC(R) device family. CSA enables the implementation of an array of capacitive sensors through switched capacitor circuitry, an analog multiplexer and digital counting function.
Sheet1resistance of resistorTime Constant = 5.3s10v from power sup.docxmaoanderton
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Sheet1resistance of resistorTime Constant = 5.3s10v from power supply 54.37 kohmscapacitor 96.9 micro farradsY axistheoretical max 183.9 micro amps0835-0.7955515238536.610-1.61434389121016.215-2.4293808894157.8520-3.1538785998203.3925-3.9935622102251.8330-4.6100761648300.8635-5.3652150213350.4640-5.9909209211400.2545-6.6006864927450.18950-6.8804003955500.13355-7.2317982824550.10160-7.507026893860micro ampsseconds
5 10 15 20 25 30 35 40 45 50 55 60 -0.79555152381367755 -1.6143438912029549 -2.4293808893719371 -3.1538785998159584 -3.9935622102179167 -4.6100761647569461 -5.3652150213448593 -5.9909209211092715 -6.6006864927301665 -6.8804003955327699 -7.2317982823706588 -7.5070268937511528
Sheet285.5k ohms96.9 micro farrads10v from power supplyTime constant = 8.3Y axistheoretical max 117 micro amps050.18-0.8481529267823.616-1.60092722281611.324-2.3373712091244.8432-3.1852592141322.3440-3.9120230054401.1448-4.6311456724480.53456-5.3895333748560.31464-5.9205362279640.2172-6.3228216831720.14880-6.67271694800.12488-6.8496476482880.10896-6.987797986796micro ampsseconds
8 16 24 32 40 48 56 64 72 80 88 96 -0.84815292670693698 -1.6009272227661917 -2.3373712090794614 -3.185259214069216 -3.912023005428146 -4.6311456723913524 -5.3895333748196981 -5.92053622787164 -6.3228216830624246 -6.6727169400157784 -6.8496476481748561 -6.9877979866556732
Sheet384.37k ohms96.9 micro farradstime constant 5.310vx axisy axis4.855-0.66358837837.7410-1.48722027978.9815-2.28278246579.520-2.99573227369.7625-3.7297014486voltsseconds
5 10 15 20 25 -0.6635883783184009 -1.4872202797098513 -2.2827824656978661 -2.99573227355399 -3.7297014486341906
Sheet4resistance 85.5k ohm96.9 micro farradtime constant = 8.3s10vx axisy axis5.348-0.76356964497.8916-1.55589714559.0624-2.36446049679.5432-3.07911388259.7640-3.7297014486voltsseconds
8 16 24 32 40 seconds -0.76356964485649126 -1.5558971455060702 -2.3644604967121334 -3.0791138824930413 -3.7297014486341906
R-C Circuits
Purpose: This lab will consider another electrical component with unique characteristics, the capacitor. The lab will also provide practice constructing and interpreting graphs for the purpose of circuit analysis.
Introduction: As you have learned, a capacitor in its simplest form is two parallel plates of conductive material, separated by a non-conductive material that prevents the plates from touching. Capacitance, âCâ, is measured in Farads (F), with typical values of capacitors being measured in ÎŒF. Capacitor labeling sometimes deviates from standard metric prefixes in that an upper case âMâ is often used in place of the ÎŒ symbol for micro- (x 10-6). Do not confuse it with mega- (x 10+6). A mega-Farad capacitor would be enormous, if one could even be built!
As an electrical potential (voltage) is placed across the capacitor, electrical charge flows (current) from the voltage source and builds up on the plates of the capacitor. If connected to a DC source, the current will continue to fl.
Control And Programingof Synchronous Generatorfreelay
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author: International Team
publisher: Daniel Garrido
licence: Creative Commons
place: University of Southern Denmark- Odense
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An Enhanced Flying Capacitor Multilevel Inverter fed Induction Motor DriveIDES Editor
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This paper focused on the development of
capacitor voltage balancing methods in a flying capacitor
multilevel inverter (FCMLI) fed induction motor drive.
For improving the performance of flying capacitor
multilevel inverter, a switching pattern selection scheme
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voltage fluctuation. The performance of proposed
strategies is confirmed through simulation investigations.
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Space Vector Modulation in Voltage Sourced Three Level Neutral Point Clamped ...emredurna
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The document discusses a 3-level neutral point clamped (NPC) inverter. It has three voltage levels for each phase (+E, 0, -E) and uses space vector modulation (SVM) to generate reference voltages. SVM divides the voltage space into sectors and regions, then uses different combinations of the inverter's switching states to synthesize the reference voltage over small time intervals. Dwell times are calculated to determine how long each switching state is applied. Several SVM switching sequences are presented, including a seven-segment sequence. Simulation waveforms show the output voltage and current are close to sinusoidal.
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GraphRAG for life science domain, where you retriever information from biomedical knowledge graphs using LLMs to increase the accuracy and performance of generated answers
Dive into the realm of operating systems (OS) with Pravash Chandra Das, a seasoned Digital Forensic Analyst, as your guide. đ This comprehensive presentation illuminates the core concepts, types, and evolution of OS, essential for understanding modern computing landscapes.
Beginning with the foundational definition, Das clarifies the pivotal role of OS as system software orchestrating hardware resources, software applications, and user interactions. Through succinct descriptions, he delineates the diverse types of OS, from single-user, single-task environments like early MS-DOS iterations, to multi-user, multi-tasking systems exemplified by modern Linux distributions.
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The journey concludes with a reflection on the ever-evolving landscape of OS, underscored by the emergence of real-time operating systems (RTOS) and the persistent quest for innovation and efficiency. As technology continues to shape our world, understanding the foundations and evolution of operating systems remains paramount. Join Pravash Chandra Das on this illuminating journey through the heart of computing. đ
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Spark is the widely used ETL tool for processing, indexing and ingesting data to serving stack for search. Milvus is the production-ready open-source vector database. In this talk we will show how to use Spark to process unstructured data to extract vector representations, and push the vectors to Milvus vector database for search serving.
HCL Notes und Domino Lizenzkostenreduzierung in der Welt von DLAUpanagenda
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Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-und-domino-lizenzkostenreduzierung-in-der-welt-von-dlau/
DLAU und die Lizenzen nach dem CCB- und CCX-Modell sind fĂŒr viele in der HCL-Community seit letztem Jahr ein heiĂes Thema. Als Notes- oder Domino-Kunde haben Sie vielleicht mit unerwartet hohen Benutzerzahlen und LizenzgebĂŒhren zu kĂ€mpfen. Sie fragen sich vielleicht, wie diese neue Art der Lizenzierung funktioniert und welchen Nutzen sie Ihnen bringt. Vor allem wollen Sie sicherlich Ihr Budget einhalten und Kosten sparen, wo immer möglich. Das verstehen wir und wir möchten Ihnen dabei helfen!
Wir erklĂ€ren Ihnen, wie Sie hĂ€ufige Konfigurationsprobleme lösen können, die dazu fĂŒhren können, dass mehr Benutzer gezĂ€hlt werden als nötig, und wie Sie ĂŒberflĂŒssige oder ungenutzte Konten identifizieren und entfernen können, um Geld zu sparen. Es gibt auch einige AnsĂ€tze, die zu unnötigen Ausgaben fĂŒhren können, z. B. wenn ein Personendokument anstelle eines Mail-Ins fĂŒr geteilte Mailboxen verwendet wird. Wir zeigen Ihnen solche FĂ€lle und deren Lösungen. Und natĂŒrlich erklĂ€ren wir Ihnen das neue Lizenzmodell.
Nehmen Sie an diesem Webinar teil, bei dem HCL-Ambassador Marc Thomas und Gastredner Franz Walder Ihnen diese neue Welt nĂ€herbringen. Es vermittelt Ihnen die Tools und das Know-how, um den Ăberblick zu bewahren. Sie werden in der Lage sein, Ihre Kosten durch eine optimierte Domino-Konfiguration zu reduzieren und auch in Zukunft gering zu halten.
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Letter and Document Automation for Bonterra Impact Management (fka Social Sol...Jeffrey Haguewood
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We believe integration and automation are essential to user experience and the promise of efficient work through technology. Automation is the critical ingredient to realizing that full vision. We develop integration products and services for Bonterra Case Management software to support the deployment of automations for a variety of use cases.
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Read Taking AI to the Next Level in Manufacturing to gain insights on AI adoption in the manufacturing industry, such as:
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5th LF Energy Power Grid Model Meet-up SlidesDanBrown980551
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5th Power Grid Model Meet-up
It is with great pleasure that we extend to you an invitation to the 5th Power Grid Model Meet-up, scheduled for 6th June 2024. This event will adopt a hybrid format, allowing participants to join us either through an online Mircosoft Teams session or in person at TU/e located at Den Dolech 2, Eindhoven, Netherlands. The meet-up will be hosted by Eindhoven University of Technology (TU/e), a research university specializing in engineering science & technology.
Power Grid Model
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Power Grid Model is currently being applied in a wide variety of use cases, including grid planning, expansion, reliability, and congestion studies. It can also help in analyzing the impact of renewable energy integration, assessing the effects of disturbances or faults, and developing strategies for grid control and optimization.
What to expect
For the upcoming meetup we are organizing, we have an exciting lineup of activities planned:
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Choosing The Best AWS Service For Your Website + API.pptx
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Capacitive Sensing 101
1. Capacitive Sensing 101
By (Jon Peterson, Applications Engineer, Cypress Semiconductor Corp.)
Executive Summary
Capacitive Sensing as a human-device interface is becoming increasingly popular. Capacitive sensing can be recognized in
many popular consumer products such as laptop trackpads, MP3 players, computer monitors and cell phones, but it is
certainly not limited to these applications. More and more engineers choose capacitive sensing for its flexibility, unique
human-device interface and cost reduction over mechanical switches.
Designs are likely to experience many different environmental changes, marketing requirement changes and user abuse;
choosing a device that is flexible, programmable, and upgradeable is necessary. Without question, the most flexible,
programmable and upgradeable device on the market is the Cypress Semiconductor Programmable System on a Chip
(PSoC). PSoC is a mixed-signal array which includes analog and digital resources as well as an integrated microcontroller all
on the same chip! Choosing a fixed-function device, such as an ASIC, seems like a good idea at first, but overcoming its
problems requires spending more money on hardware. A mixed-signal array device allows resolution of most issues with a
firmware change. One major advantage of having a flash-based device is that its firmware can be updated after the device
has shipped by including a bootloader. Bootloaders are valuable are worth considering on a new design.
Understanding Electric Fields
In order to understand capacitive sensing, it is first important to understand some basics about electric fields (E-Fields). It is a
fundamental fact that E-Fields take the path of least resistance. Figure 1 shows a general form of E-Fields in a capacitive
sensing design.
Figure 1. E-Fields and Parasitic Capacitance
Capacitive Sensor
Ground Plane Ground Plane
E-Field Lines
E-Fields form from the greatest potential to the least potential. Figure 1 shows E-Field lines from the capacitive sensor to
ground. Measuring the capacitance at this point yields the parasitic capacitance. Parasitic capacitance is the capacitance of
the sensor, without a conductive object present. Figure 2 shows the effect of a conductive object in the same system.
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2. Figure 2. E-Fields with a finger present
Ground Plane Button Ground Plane
E-Field Lines
The conductive object allows an increased number of E-Field lines to travel between the sensor and ground. This greater
concentration of E-Field lines results in a greater capacitance measured at the sensor. In human interface devices, the
conductive object is typically a human finger, hand, foot, etc.
Measuring a Fixed Capacitance
It is important to understand how to measure a fixed capacitance. One of the most fundamental capacitor equations is shown
in Equation 1. Differentiating both sides with respect to time, results in Equation 2. Since a static capacitance is being
dC dq
measured, equals zero and the equation simplifies to Equation 3. is more commonly called current, i, allowing one
dt dt
final simplification to Equation 4. Equation 4 is another of the most important capacitor equations. Rearranging Equation 4
yields Equation 5 which bares a striking resemblance to the formula for a line, y = mx + b. Figure 3 shows capacitors being
charged by a constant current source.
dq dC dV dq dV dV i
q = C *V =V * +C* =C* i =C* v(t ) = *t
dt dt dt dt dt dt C
Equation 1
Equation 2 Equation 3 Equation 4 Equation 5
The slope, m, of the line is current divided by capacitance. Applying constant current to the capacitor yields a linear slope.
Changing the capacitance and keeping the source current constant causes the slope of the line to change. For the same
current, and an increase in capacitance, the slope of the line will become more gradual as shown in Figure 3.
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3. Figure 3. Voltage ramp on different capacitors
v(t)
C1
C2
C3
t
C1 < C2 < C3
Measurement Methods
Two measurements are necessary to determine the presence or absence of a conductive object on a sensor: the parasitic
capacitance and the capacitance due to the conductive object. Taking Equation 4 and rearranging it results in Equation 6.
ât
C = i*
âV
Equation 6
If the supply current, i, and the time elapsed, ât, are known, it is possible to measure the voltage change, âV. Once a
measurement for âV has been made, solving for the capacitance is simple.
The method utilizing Equation 6 is simple; a more advanced solution is to use a relaxation oscillator [Figure 4].
Figure 4. CapSense Relaxation Oscillator
Isrc
Capacitive
Sensor
Bus
Triangle Wave Pulse Train
Co
m pa
rat
o r
Reset
Capacitive S Y SCLK
Sensor
Vref 16-Bit
PWM
COUNTER
Compare E nable
O ut
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4. The current source, Isrc, provides the constant current to charge the capacitor. Isrc is connected to a bus which allows one or
more capacitors to be connected at a time. The reset switch allows the capacitors connected to the bus to be drained. Each
capacitive sensor is connected to the bus one at a time. When a sensor is first connected, Isrc applies constant current to the
capacitor to generate the ramp shown in Figure 3. Once the voltage reaches a predefined reference level, Vref, the comparator
trips and restarts the charging sequence by draining the sensor capacitor to ground. Figure 5 shows the charging sequence
and comparator trip level.
Figure 5. Pulse train frequencies with different capacitors
v(t) v(t)
Com parator Com parator
Out O ut
t t
v(t) v(t)
Vref Vref
t t
C1 C2 > C1
The pulse train's frequency decreases with a greater capacitance. The pulse train is tied to the clock input of a PWM. For a
fixed duty cycle, the PWM is high longer when measuring a greater capacitance. The output of the PWM enables a 16-bit
counter. Figure 6 shows how the PWM enable affects the counter. The counter value is greater for C2 than C1.
Figure 6. PWM Enable and Counter
After the PWM disables the counter, the counter value is stored for processing. Now that the counter value has been stored,
the circuit has undergone a full analog to digital conversion; the capacitance is stored as a digital value.
Processing the Data
Once the capacitance is stored as a digital value (raw counts), the next step is to process the data. In order for the
capacitance value to be meaningful, it must be compared to something else. Equation 7 shows the capacitance ratio.
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5. Cconductive
âC =
C parasitic
Equation 7
The capacitance due to the conductive object, Cconductive, must be compared to the capacitance occurring naturally in the
system, Cparasitic. In order to keep track of the parasitic capacitance as it changes with time, its measured value is stored in a
variable called a baseline. A baseline keeps track of the slow changes in parasitic capacitance due to environmental effects
such as temperature changes. A baseline is analogous to analog ground; the baseline does not need to be zero, but it serves
as the reference for all capacitive measurements.
There are multiple methods for storing the measured value into the baseline variable; each method is essentially a low-pass
filter. An example is an Infinite Impulse Response (IIR) filter. The IIR filter follows the simple equation shown in Equation 8.
The CurrentMeasurement variable is equal to the present measured value for the raw counts.
3 1
Baseline (n) = * Baseline(n â 1) + * CurrentMeasurement
4 4
Equation 8
Once a stable baseline has been established the next step is to define the level at which a finger press will be detected. The
best way to detect a finger press is to define two threshold values, one at which the signal is considered to be noise and the
other where the signal is considered to be a finger press (or presence of a conductive object). Figure 7 shows each of the
thresholds in a capacitive sensing system. Care should be taken to choose the correct levels of these thresholds as they
affect the sensitivity and performance of the system. The thresholds are relative to the baseline. To add hysteresis, detect a
finger press when the raw counts break above the finger threshold, and detect the off state when the finger press falls below
the noise threshold.
Figure 7. Thresholds in a capacitive sensing system
PCB Design Basics
Capacitive sensors can be constructed from many different media, such as copper,ITO and printed ink. Copper capacitive
sensors can be implemented on standard FR4 PCBs as well as on flexible material. ITO allows the capacitive sensor to be up
to 90% transparent (for single layer solutions).
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6. The size and spacing of the capacitive sensor are both very important to the sensor's performance. Figure 8 shows the
recommended sensor spacing.
Figure 8.
0.5mm
10mm
40% hatched Ground Plane 40% hatched Ground Plane
Capacitive Sensor
In addition to the size of the sensor, and its spacing relative to the ground plane, the type of ground plane used is very
important. Since the parasitic capacitance of the sensor is related to the E-Field's path to ground, it is important to choose a
ground plane that limits the concentration of E-Field lines without a conductive object present. Equation 7, shows decreasing
the parasitic capacitance increases the device's sensitivity (greater âC). The recommended ground plane for capacitive
sensors is a 40% fill, hatched ground plane. Leave some ground plane intact so that the conductive object is still able to
provide a low-resistance path to ground without affecting other circuit elements. For a more detailed description of capacitive
sensor layout, please refer to the Cypress Semiconductor Application Note AN2292.
Troubleshooting and Debugging
It is difficult to account for all environmental effects in the initial design phase. There may be some adjustments required for
the noise and finger thresholds. Care should be taken to test the system across the full operating temperature range and in
noisy environments.
Conclusion
Designing a capacitance sensing system is fairly straightforward. First, pick the type of sensing material (FR4, Flex, ITO, etc).
Second, understand the environment the device will operate in. Understand the full operating temperature range, what radio
frequencies are present and how the user will interact with the interface. Third, choose an integrated circuit that will be able to
handle the demands of a changing environment and is upgradeable. The Cypress Semiconductor Programmable System on
a Chip, Mixed Signal Array, is a configurable device which includes royalty-free source code for implementing a capacitive
sensing solution. Fourth, do not make compromises with your PCB design that will affect capacitance sensing performance.
Make sure to pay attention to the layout guidelines defined in Cypress application note AN2292. Fifth, spend the time to quot;tunequot;
your system. Make sure the design meets the environment requirements. Finally, be patient while troubleshooting. If you are
not familiar with capacitance sensing, take the time to understand it. Cypress Semiconductor makes several capacitive
sensing evaluation boards, such as the CY3212 and CY3214. Cypress also provides free source code examples that ship
with these evaluation kits. To view the source code online, please visit http://www.cypress.com/capsense/ and click on the
quot;Applicationsquot; link.
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