Current-Mode Vs. Voltage-Mode Control In Synchronous Buck Converters by Brian Lynch, Texas Instruments Incorporated
|
|
- Elaine Quinn
- 7 years ago
- Views:
Transcription
1 Current-Mode Vs. Voltage-Mode Control In Synchronous Buck Converters by Brian Lynch, Texas Instruments Incorporated For the past twenty years, feedback current-mode control (CMC) has been the method of choice for many high-performance power supply applications. But is it the optimum choice for all power supplies? Here we discuss the pros and cons of CMC Vs. voltagemode control (VMC) as applied to general purpose dc-dc synchronous buck converters. The choice of whether to implement CMC or VMC as the feedback control method in a synchronous buck dc-dc converter is based on a number of considerations. While the perceived advantage of CMC is better feedback loop response, today s high-frequency VMC controlled converters closely rival their CMC counterparts. Fig. 1 illustrates the difference in feedback loop performance for a 3.3-V to 1.8-V dc-dc converter with a 1-A output using CMC and VMC and operating at 6 khz. Since the conversion ratio is above 5% duty cycle, a small amount of slope compensation is added to the CMC loop. In textbook fashion the CMC control-to-output gain is higher at low frequencies and has a zero gain crossover frequency much higher than the VMC counterpart has. Gain (db) CMC Gain VMC Gain CMC Phase VMC Phase Fig. 1: CMC And VMC Control-To-Output Loop Gain/Phase The difference can be narrowed (see Fig. 2) by using Type 3 compensation around the VMC error amplifier when the overall loop performance matches that of a CMC system, albeit at the expense of requiring a higher-bandwidth amplifier.
2 Gain (db) VMC Gain CMC Gain VMC Phase CMC Phase Fig. 2: CMC And VMC Closed-Loop Gain/Phase Notice that near the L-C pole frequency the CMC closed-loop phase response is more smooth than the closed-loop phase response of the VMC system, due to L-C resonance combined with the HF pole-then-zero of the Type 3 compensation (see Fig. 3.) Ringing in the output voltage during load transients will be less damped than with the CMC system. Gain (db) VMC E/A Gain CMC E/A Gain VMC E/A Phase CMC E/A Phase Fig. 3 Error-Amplifier Gain And Phase
3 Converters with a wide input-voltage range must compensate for open-loop gain variation by selecting compensation components either for worst-case (high-input voltage) or by including a gain-compensating circuit. With VMC, since converter gain is dependent on the input voltage and the PWM ramp amplitude, input-voltage feed-forward is used. Conversely, peak CMC directly provides input-voltage gain compensation by the change in inductor slope during the switch ON time. While in practice this compensation is not as effective as pure voltage feed-forward, it is nonetheless free in CMC. From a signal path standpoint in VMC, a load current change must first have an effect on the output voltage before the voltage amplifier can react and make a correction. CMC on the other hand senses a change in load current directly so the voltage amplifier does not need to react in order for the loop to make a correction. This cause-and-then-react approach makes VMC slower to respond than CMC with very high-speed load transients. One key differentiator in applying either of the two control methods is current sensing. CMC requires accurate current sensing for control loop stability, and relatively large voltage levels are required to ensure that a good SNR is maintained at light loads. This voltage level with the load current at full load can result in significant power loss. To reduce the power loss, a smaller sense element may be used. However, to increase the sensed signal to a useable level requires a high bandwidth current-sense amplifier. In most applications, a small amount of slope compensation is also required to ensure loop stability. Generally this is accomplished by summing in a small amount of signal from an oscillator ramp into the measured current signal. Output voltage regulation is independent of current with VMC, so relatively crude current sensing may be acceptable since it is only necessary for output overload protection. This can save considerable circuit complexity and reduce circuit power loss. A B SW1 Lout Vin Cin SW2 D Cout E ILoad C Fig. 4: Alternate Points To Measure Current - With Different Tradeoffs In location A (see Fig. 4), average input current is monitored. While this is useful for controlling inrush current, it is not a very useful place for current mode control. When
4 used for current limit protection, input power is limited instead of output fault current and therefore this method implements a power limiting approach to fault protection. To keep the power limiting constant with input-voltage variation, additional circuitry is required to reduce the limiting threshold level with increasing input voltage. Location B, in series with the upper MOSFET switch (or it may be the RdsON of the switch itself while the MOSFET is ON) is a popular location for current sensing when peak current mode control is implemented. Since slope information is available, ac feedback information is available for the control loop. A drawback at narrow pulse widths (due to high input-to-output conversion ratios or high operating frequency) is that the amount of useable slope information can become virtually non-existent due to circuit ringing and blanking time intervals. The ON impedance of a MOSFET can be used as a sense element with no penalty in power loss or circuit cost; however component variance, RdsON temperature coefficient and the ringing seen at the switch node can all affect feedback loop performance. If this approach is used, then slope compensation must be added for duty cycles of greater than 5%. Current measured at Location C is also peak current, but it is the peak current measured during the OFF time of the upper switch instead of the ON time as is the case in B. In this way CMC applies the same OFF time current information to the feedback loop so long as leading edge PWM is the control technique, instead of the more commonly used trailing edge PWM when slope compensation must be added for duty cycles of less than 5% Current measured in location D is the output current directly and is therefore the most attractive from a feedback standpoint. Here average dc output current as well as ac slope information is available and so any change in the output load current is quickly translated into a feedback response. Unfortunately, since the current is mostly dc at this point, current sensing at this location is also more dissipative than at the first three. A low value resistor may be used as a sense element at the expense of low current noise immunity, or the dc resistance of the inductor may be used, at the expense of additional filtering. Location E carries dc load current information and cannot be used for CMC, but it can be used for applications requiring a slow current sharing loop. There is a similar power loss issue as in D. However, since no high frequency control information is required, then filtering may be applied and light load SNR is not an issue. For general purpose single output dc-dc converters, the overall advantage goes with VMC. The feedback network, even with a Type 3 compensation network around the voltage-error amplifier, is relatively simple to compensate. In many ways it is simpler than compensating a current loop, plus a voltage loop, plus adding slope compensation. This, along with the improved noise immunity at light loads, makes VMC attractive from a circuit performance standpoint. From a customer point of view, having features such as slope compensation or input voltage feed-forward internally added by an IC vendor is both a plus and a minus. On the plus side the customer does not have to add any components. On the minus side whatever
5 manner the IC vendor chooses to implement the feature is the manner the customer is stuck with. Perhaps for a specific approach the manner is acceptable, but what of the corners of operation where the customer has to work around the built-in feature? A good parallel to this is internal feedback compensation Vs. external compensation. In some cases, it can reduce component count; however, it also severely limits the selection of the operating frequency, the filter inductor, and the output capacitors. The best compromise is to have a feature included in the IC with the means for a customer to adjust its effect. From an implementation standpoint the current sensing requirements of CMC require higher accuracy than those of VMC, so higher power loss or circuit complexity is likely. For most general purpose applications, where only basic current overload protection is required, low-value/low-cost sensing elements are used without worrying about noise sensitivity at light loads. If tight tolerance in overload protection is a requirement, then either VMC or CMC can be designed to meet that need equally. About the author Brian Lynch is systems team leader, Dc-Dc Control Products, for Texas Instruments. brian_lynch@ti.com
Designing Stable Compensation Networks for Single Phase Voltage Mode Buck Regulators
Designing Stable Compensation Networks for Single Phase Voltage Mode Buck Regulators Technical Brief December 3 TB47. Author: Doug Mattingly Assumptions This Technical Brief makes the following assumptions:.
More information3-Phase Synchronous PWM Controller IC Provides an Integrated Solution for Intel VRM 9.0 Design Guidelines
3-Phase Synchronous PWM Controller IC Provides an Integrated Solution for Intel VRM 9.0 Design Guidelines Odile Ronat International Rectifier The fundamental reason for the rapid change and growth in information
More informationTechnical Note #3. Error Amplifier Design and Applications. Introduction
Technical Note #3 Error Amplifier Design and Applications Introduction All regulating power supplies require some sort of closed-loop control to force the output to match the desired value. Both digital
More informationCapacitor Ripple Current Improvements
Capacitor Ripple Current Improvements The multiphase buck regulator topology allows a reduction in the size of the input and put capacitors versus single-phase designs. By quantifying the input and put
More informationApplication of network analyzer in measuring the performance functions of power supply
J Indian Inst Sci, July Aug 2006, 86, 315 325 Indian Institute of Science Application of network analyzer in measuring the performance functions of power supply B SWAMINATHAN* AND V RAMANARAYANAN Power
More informationMP2259 1A, 16V, 1.4MHz Step-Down Converter
MP59 1A, 1V, 1.MHz Step-Down Converter TM The Future of Analog IC Technology DESCRIPTION The MP59 is a monolithic integrated stepdown switch mode converter with an internal power MOSFET. It achieves 1A
More informationDesign A High Performance Buck or Boost Converter With Si9165
Design A High Performance Buck or Boost Converter With Si9165 AN723 AN723 by Kin Shum INTRODUCTION The Si9165 is a controller IC designed for dc-to-dc conversion applications with 2.7- to 6- input voltage.
More informationAC/DC Power Supply Reference Design. Advanced SMPS Applications using the dspic DSC SMPS Family
AC/DC Power Supply Reference Design Advanced SMPS Applications using the dspic DSC SMPS Family dspic30f SMPS Family Excellent for Digital Power Conversion Internal hi-res PWM Internal high speed ADC Internal
More informationPower supply output voltages are dropping with each
DESIGNER S SERIES Second-Stage LC Filter Design First Inductor by Dr. Ray Ridley First Capacitor Power supply output voltages are dropping with each new generation of Integrated Circuits (ICs). Anticipated
More informationU-97 APPLICATION NOTE MODELLING, ANALYSIS AND COMPENSATION OF THE CURRENT-MODE CONVERTER 3-43. Abstract
APPLICATION NOTE MODELLING, ANALYSIS AND COMPENSATION OF THE CURRENT-MODE CONVERTER U-97 Abstract As current-mode conversion increases in popularity, several peculiarities associated with fixed-frequency,
More informationDatasheet. 2A 380KHZ 20V PWM Buck DC/DC Converter. Features
General Description Features The is a 380 KHz fixed frequency monolithic step down switch mode regulator with a built in internal Power MOSFET. It achieves 2A continuous output current over a wide input
More informationInput and Output Capacitor Selection
Application Report SLTA055 FEBRUARY 2006 Input and Output Capacitor Selection Jason Arrigo... PMP Plug-In Power ABSTRACT When designing with switching regulators, application requirements determine how
More informationLine Reactors and AC Drives
Line Reactors and AC Drives Rockwell Automation Mequon Wisconsin Quite often, line and load reactors are installed on AC drives without a solid understanding of why or what the positive and negative consequences
More informationSwitch Mode Power Supply Topologies
Switch Mode Power Supply Topologies The Buck Converter 2008 Microchip Technology Incorporated. All Rights Reserved. WebSeminar Title Slide 1 Welcome to this Web seminar on Switch Mode Power Supply Topologies.
More informationUnderstanding Power Impedance Supply for Optimum Decoupling
Introduction Noise in power supplies is not only caused by the power supply itself, but also the load s interaction with the power supply (i.e. dynamic loads, switching, etc.). To lower load induced noise,
More informationInrush Current. Although the concepts stated are universal, this application note was written specifically for Interpoint products.
INTERPOINT Although the concepts stated are universal, this application note was written specifically for Interpoint products. In today s applications, high surge currents coming from the dc bus are a
More informationPower Supplies. 1.0 Power Supply Basics. www.learnabout-electronics.org. Module
Module 1 www.learnabout-electronics.org Power Supplies 1.0 Power Supply Basics What you ll learn in Module 1 Section 1.0 Power Supply Basics. Basic functions of a power supply. Safety aspects of working
More informationWHY DIFFERENTIAL? instruments connected to the circuit under test and results in V COMMON.
WHY DIFFERENTIAL? Voltage, The Difference Whether aware of it or not, a person using an oscilloscope to make any voltage measurement is actually making a differential voltage measurement. By definition,
More informationA Simple Current-Sense Technique Eliminating a Sense Resistor
INFINITY Application Note AN-7 A Simple Current-Sense Technique Eliminating a Sense Resistor Copyright 998 A SIMPE CURRENT-SENSE TECHNIQUE EIMINATING A SENSE RESISTOR INTRODUCTION A sense resistor R S,
More informationSimple PWM Boost Converter with I/O Disconnect Solves Malfunctions Caused when V OUT <V IN
Simple PWM Boost Converter with I/O Disconnect Solves Malfunctions Caused when V OUT
More informationIntroduction to SMPS Control Techniques
Introduction to SMPS Control Techniques 2006 Microchip Technology Incorporated. All Rights Reserved. Introduction to SMPS Control Techniques Slide 1 Welcome to the Introduction to SMPS Control Techniques
More informationULRASONIC GENERATOR POWER CIRCUITRY. Will it fit on PC board
ULRASONIC GENERATOR POWER CIRCUITRY Will it fit on PC board MAJOR COMPONENTS HIGH POWER FACTOR RECTIFIER RECTIFIES POWER LINE RAIL SUPPLY SETS VOLTAGE AMPLITUDE INVERTER INVERTS RAIL VOLTAGE FILTER FILTERS
More informationChapter 4. LLC Resonant Converter
Chapter 4 LLC Resonant Converter 4.1 Introduction In previous chapters, the trends and technical challenges for front end DC/DC converter were discussed. High power density, high efficiency and high power
More informationLM2576R. 3.0A, 52kHz, Step-Down Switching Regulator FEATURES. Applications DESCRIPTION TO-220 PKG TO-220V PKG TO-263 PKG ORDERING INFORMATION
LM2576 FEATURES 3.3, 5.0, 12, 15, and Adjustable Output ersions Adjustable ersion Output oltage Range, 1.23 to 37 +/- 4% AG10Maximum Over Line and Load Conditions Guaranteed 3.0A Output Current Wide Input
More informationTDA4605 CONTROL CIRCUIT FOR SWITCH MODE POWER SUPPLIES USING MOS TRANSISTORS
CONTROL CIRCUIT FOR SWITCH MODE POWER SUPPLIES USING MOS TRANSISTORS Fold-Back Characteristic provides Overload Protection for External Diodes Burst Operation under Short-Circuit and no Load Conditions
More informationLM 358 Op Amp. If you have small signals and need a more useful reading we could amplify it using the op amp, this is commonly used in sensors.
LM 358 Op Amp S k i l l L e v e l : I n t e r m e d i a t e OVERVIEW The LM 358 is a duel single supply operational amplifier. As it is a single supply it eliminates the need for a duel power supply, thus
More informationHigh Voltage Power Supplies for Analytical Instrumentation
ABSTRACT High Voltage Power Supplies for Analytical Instrumentation by Cliff Scapellati Power supply requirements for Analytical Instrumentation are as varied as the applications themselves. Power supply
More informationHarmonics and Noise in Photovoltaic (PV) Inverter and the Mitigation Strategies
Soonwook Hong, Ph. D. Michael Zuercher Martinson Harmonics and Noise in Photovoltaic (PV) Inverter and the Mitigation Strategies 1. Introduction PV inverters use semiconductor devices to transform the
More informationProgrammable-Gain Transimpedance Amplifiers Maximize Dynamic Range in Spectroscopy Systems
Programmable-Gain Transimpedance Amplifiers Maximize Dynamic Range in Spectroscopy Systems PHOTODIODE VOLTAGE SHORT-CIRCUIT PHOTODIODE SHORT- CIRCUIT VOLTAGE 0mV DARK ark By Luis Orozco Introduction Precision
More informationArticle from Micrel. A new approach to the challenge of powering cellular M2M modems By Anthony Pele Senior Field Applications Engineer, Micrel
Article from Micrel A new approach to the challenge of powering cellular M2M modems By Anthony Pele Senior Field Applications Engineer, Micrel www.micrel.com Industrial applications for machine-to-machine
More informationZero voltage drop synthetic rectifier
Zero voltage drop synthetic rectifier Vratislav Michal Brno University of Technology, Dpt of Theoretical and Experimental Electrical Engineering Kolejní 4/2904, 612 00 Brno Czech Republic vratislav.michal@gmail.com,
More informationCreate Colorful and Bright LED Light with an LED Matrix Dimmer
Create Colorful and Bright LED Light with an LED Matrix Dimmer By Keith Szolusha, Applications Engineering Section Leader, Power Products, Linear Technology RGB LEDs are used in projector, architectural,
More informationApplication Note 142 August 2013. New Linear Regulators Solve Old Problems AN142-1
August 2013 New Linear Regulators Solve Old Problems Bob Dobkin, Vice President, Engineering and CTO, Linear Technology Corp. Regulators regulate but are capable of doing much more. The architecture of
More informationWhen the Power Fails: Designing for a Smart Meter s Last Gasp
When the Power Fails: Designing for a Smart Meter s Last Gasp Daniel Pruessner 1/10/2012 5:25 PM EST Overview Smart meter designers have an unusual predicament: The meter is powered from the same bus that
More informationApplication Note SAW-Components
Application Note SAW-Components Principles of SAWR-stabilized oscillators and transmitters. App: Note #1 This application note describes the physical principle of SAW-stabilized oscillator. Oscillator
More informationDDR SDRAM Memory Termination USING THE LX1672 AND LX1673 FOR DDR SDRAM MEMORY TERMINATION INTEGRATED PRODUCTS. Microsemi
AN-17 USING THE LX1672 AND LX1673 FOR DDR SDRAM MEMORY TERMINATION LX1672 Protected by US Patents: 6,285,571 & 6,292,378 INTEGRATED PRODUCTS Page 1 TABLE OF CONTENTS 1.0 INTRODUCTION... 3 2.0 SDR vs DDR
More informationOp Amp Circuit Collection
Op Amp Circuit Collection Note: National Semiconductor recommends replacing 2N2920 and 2N3728 matched pairs with LM394 in all application circuits. Section 1 Basic Circuits Inverting Amplifier Difference
More informationSeries AMLDL-Z Up to 1000mA LED Driver
FEATURES: Click on Series name for product info on aimtec.com Series Up to ma LED Driver Models Single output Model Input Voltage (V) Step Down DC/DC LED driver Operating Temperature range 4ºC to 85ºC
More informationMAS.836 HOW TO BIAS AN OP-AMP
MAS.836 HOW TO BIAS AN OP-AMP Op-Amp Circuits: Bias, in an electronic circuit, describes the steady state operating characteristics with no signal being applied. In an op-amp circuit, the operating characteristic
More informationMP1541 1.3MHz Boost Converter
MP5.3MHz Boost Converter The Future of Analog IC Technology DESCRIPTION The MP5 is a 5-pin thin SOT3 current mode step up converter intended for small, low power applications. The MP5 switches at.3mhz
More informationBi-directional Power System for Laptop Computers
Bi-directional Power System for Laptop Computers Terry L. Cleveland Staff Applications Engineer Microchip Technology Inc. Terry.Cleveland@Microchip.com Abstract- Today the typical laptop computer uses
More informationLaboratory 4: Feedback and Compensation
Laboratory 4: Feedback and Compensation To be performed during Week 9 (Oct. 20-24) and Week 10 (Oct. 27-31) Due Week 11 (Nov. 3-7) 1 Pre-Lab This Pre-Lab should be completed before attending your regular
More informationIntroduction to Power Supplies
Introduction to Power Supplies INTRODUCTION Virtually every piece of electronic equipment e g computers and their peripherals calculators TV and hi-fi equipment and instruments is powered from a DC power
More informationLM101A LM201A LM301A Operational Amplifiers
LM101A LM201A LM301A Operational Amplifiers General Description The LM101A series are general purpose operational amplifiers which feature improved performance over industry standards like the LM709 Advanced
More informationLecture 24. Inductance and Switching Power Supplies (how your solar charger voltage converter works)
Lecture 24 Inductance and Switching Power Supplies (how your solar charger voltage converter works) Copyright 2014 by Mark Horowitz 1 Roadmap: How Does This Work? 2 Processor Board 3 More Detailed Roadmap
More informationDC/DC power modules basics
DC/DC power modules basics Design Note 024 Ericsson Power Modules General Abstract This design note covers basic considerations for the use of on-board switch mode DC/DC power modules, also commonly known
More informationOp-Amp Simulation EE/CS 5720/6720. Read Chapter 5 in Johns & Martin before you begin this assignment.
Op-Amp Simulation EE/CS 5720/6720 Read Chapter 5 in Johns & Martin before you begin this assignment. This assignment will take you through the simulation and basic characterization of a simple operational
More informationHigh Performance ZVS Buck Regulator Removes Barriers To Increased Power Throughput In Wide Input Range Point-Of-Load Applications
White paper High Performance ZVS Buck Regulator Removes Barriers To Increased Power Throughput In Wide Input Range Point-Of-Load Applications Written by: C. R. Swartz Principal Engineer, Picor Semiconductor
More information1ED Compact A new high performance, cost efficient, high voltage gate driver IC family
1ED Compact A new high performance, cost efficient, high voltage gate driver IC family Heiko Rettinger, Infineon Technologies AG, Am Campeon 1-12, 85579 Neubiberg, Germany, heiko.rettinger@infineon.com
More informationApplication Note, Rev.1.0, September 2008 TLE8366. Application Information. Automotive Power
Application Note, Rev.1.0, September 2008 TLE8366 Automotive Power Table of Contents 1 Abstract...3 2 Introduction...3 3 Dimensioning the Output and Input Filter...4 3.1 Theory...4 3.2 Output Filter Capacitor(s)
More informationMP2456 0.5A, 50V, 1.2MHz Step-Down Converter in a TSOT23-6
MP2456 0.5A, 50V, 1.2MHz Step-Down Converter in a TSOT23-6 DESCRIPTION The MP2456 is a monolithic, step-down, switchmode converter with a built-in power MOSFET. It achieves a 0.5A peak-output current over
More informationTheory of Operation. Figure 1 illustrates a fan motor circuit used in an automobile application. The TPIC2101. 27.4 kω AREF.
In many applications, a key design goal is to minimize variations in power delivered to a load as the supply voltage varies. This application brief describes a simple DC brush motor control circuit using
More informationMIC33050. General Description. Features. Applications. Typical Application. 4MHz Internal Inductor PWM Buck Regulator with HyperLight Load
4MHz Internal Inductor PWM Buck Regulator with HyperLight Load General Description The Micrel is a high-efficiency 600mA PWM synchronous buck (step-down) regulator with internal inductor featuring HyperLight
More informationJosé A. Cobos, Pedro Alou Centro de Electrónica Industrial (CEI)
José A. Cobos, Pedro Alou Centro de (CEI) Universidad Politécnica de Madrid www.cei.upm.es September 2008 Outline Motivation Cout, Current & voltage steps Optimal time control Analog implementations V
More informationModification Details.
Front end receiver modification for DRM: AKD Target Communications receiver. Model HF3. Summary. The receiver was modified and capable of receiving DRM, but performance was limited by the phase noise from
More informationAccurate Point-of-Load Voltage Regulation Using Simple Adaptive Loop Feedback
APPLCATON NOTE AN:04 Accurate Point-of-Load oltage egulation Using imple Adaptive Loop eedback Maurizio alato Principal Engineer August 009 Contents Page ntroduction ntroduction 1 Adaptive Loop egulation
More informationEliminate Ripple Current Error from Motor Current Measurement
Eliminate ipple Current Error from Motor Current Measurement Eric Persson, Toshio Takahashi Advanced Development Group International ectifier Corp. U..A. INTODUCTION Most motor drives today use measured
More informationSince any real component also has loss due to the resistive component, the average power dissipated is 2 2R
Quality factor, Q Reactive components such as capacitors and inductors are often described with a figure of merit called Q. While it can be defined in many ways, it s most fundamental description is: Q
More informationProgrammable Single-/Dual-/Triple- Tone Gong SAE 800
Programmable Single-/Dual-/Triple- Tone Gong Preliminary Data SAE 800 Bipolar IC Features Supply voltage range 2.8 V to 18 V Few external components (no electrolytic capacitor) 1 tone, 2 tones, 3 tones
More informationLecture 24: Oscillators. Clapp Oscillator. VFO Startup
Whites, EE 322 Lecture 24 Page 1 of 10 Lecture 24: Oscillators. Clapp Oscillator. VFO Startup Oscillators are circuits that produce periodic output voltages, such as sinusoids. They accomplish this feat
More information6.101 Final Project Report Class G Audio Amplifier
6.101 Final Project Report Class G Audio Amplifier Mark Spatz 4/3/2014 1 1 Introduction For my final project, I designed and built a 150 Watt audio amplifier to replace the underpowered and unreliable
More informationChapter 11 Current Programmed Control
Chapter 11 Current Programmed Control Buck converter v g i s Q 1 D 1 L i L C v R The peak transistor current replaces the duty cycle as the converter control input. Measure switch current R f i s Clock
More informationTransmission Line Terminations It s The End That Counts!
In previous articles 1 I have pointed out that signals propagating down a trace reflect off the far end and travel back toward the source. These reflections can cause noise, and therefore signal integrity
More information1. Oscilloscope is basically a graph-displaying device-it draws a graph of an electrical signal.
CHAPTER 3: OSCILLOSCOPE AND SIGNAL GENERATOR 3.1 Introduction to oscilloscope 1. Oscilloscope is basically a graph-displaying device-it draws a graph of an electrical signal. 2. The graph show signal change
More informationTM MP2305 2A, 23V SYNCHRONOUS RECTIFIED, STEP-DOWN CONVERTER
The Future of Analog IC Technology TM TM MP305 A, 3 Synchronous Rectified Step-Down Converter DESCRIPTION The MP305 is a monolithic synchronous buck regulator. The device integrates 30mΩ MOSFETS that provide
More informationEXPERIMENT NUMBER 5 BASIC OSCILLOSCOPE OPERATIONS
1 EXPERIMENT NUMBER 5 BASIC OSCILLOSCOPE OPERATIONS The oscilloscope is the most versatile and most important tool in this lab and is probably the best tool an electrical engineer uses. This outline guides
More informationModule 11: Conducted Emissions
Module 11: Conducted Emissions 11.1 Overview The term conducted emissions refers to the mechanism that enables electromagnetic energy to be created in an electronic device and coupled to its AC power cord.
More informationAN-8019 Reliable USB Modem Design Using the Combination of an Integrated Load Switch and a Buck Converter
www.fairchildsemi.com AN-8019 Reliable USB Modem Design Using the Combination of an Integrated Load Switch and a Buck Converter Introduction In the portable electronics market, a wireless network allows
More informationCurrent vs. Voltage Feedback Amplifiers
Current vs. ltage Feedback Amplifiers One question continuously troubles the analog design engineer: Which amplifier topology is better for my application, current feedback or voltage feedback? In most
More informationElectronics for Analog Signal Processing - II Prof. K. Radhakrishna Rao Department of Electrical Engineering Indian Institute of Technology Madras
Electronics for Analog Signal Processing - II Prof. K. Radhakrishna Rao Department of Electrical Engineering Indian Institute of Technology Madras Lecture - 18 Wideband (Video) Amplifiers In the last class,
More informationVICOR WHITE PAPER. The Sine Amplitude Converter Topology Provides Superior Efficiency and Power Density in Intermediate Bus Architecture Applications
The Sine Amplitude Converter Topology Provides Superior Efficiency and Power Density in Intermediate Bus Architecture Applications Maurizio Salato, Applications Engineering, Vicor Corporation Contents
More informationUse and Application of Output Limiting Amplifiers (HFA1115, HFA1130, HFA1135)
Use and Application of Output Limiting Amplifiers (HFA111, HFA110, HFA11) Application Note November 1996 AN96 Introduction Amplifiers with internal voltage clamps, also known as limiting amplifiers, have
More informationLoop Bandwidth and Clock Data Recovery (CDR) in Oscilloscope Measurements. Application Note 1304-6
Loop Bandwidth and Clock Data Recovery (CDR) in Oscilloscope Measurements Application Note 1304-6 Abstract Time domain measurements are only as accurate as the trigger signal used to acquire them. Often
More informationDesign and Construction of Variable DC Source for Laboratory Using Solar Energy
International Journal of Electronics and Computer Science Engineering 228 Available Online at www.ijecse.org ISSN- 2277-1956 Design and Construction of Variable DC Source for Laboratory Using Solar Energy
More information1.5A Very L.D.O Voltage Regulator LM29150/29151/29152
FEATURES High Current Capability 1.5A Low Dropout Voltage 350mV Low Ground Current Accurate 1% Guaranteed Initial Tolerance Extremely Fast Transient Response Reverse-Battery and "Load Dump" Protection
More informationNational Semiconductor Power Products - Seminar 3 (LED Lighting)
National Semiconductor Power Products - Seminar 3 (LED Lighting) Dr. Iain Mosely Converter Technology Ltd. Slide 1 Overview Background on LEDs Power Electronics for Driving LEDs LED Driver Specific Solutions
More informationPrecision Diode Rectifiers
by Kenneth A. Kuhn March 21, 2013 Precision half-wave rectifiers An operational amplifier can be used to linearize a non-linear function such as the transfer function of a semiconductor diode. The classic
More informationAPPLICATION NOTE ULTRASONIC CERAMIC TRANSDUCERS
APPLICATION NOTE ULTRASONIC CERAMIC TRANSDUCERS Selection and use of Ultrasonic Ceramic Transducers The purpose of this application note is to aid the user in the selection and application of the Ultrasonic
More informationReading: HH Sections 4.11 4.13, 4.19 4.20 (pgs. 189-212, 222 224)
6 OP AMPS II 6 Op Amps II In the previous lab, you explored several applications of op amps. In this exercise, you will look at some of their limitations. You will also examine the op amp integrator and
More informationUNISONIC TECHNOLOGIES CO., LTD
UPS61 UNISONIC TECHNOLOGIES CO., LTD HIGH PERFORMANCE CURRENT MODE POWER SWITCH DESCRIPTION The UTC UPS61 is designed to provide several special enhancements to satisfy the needs, for example, Power-Saving
More informationMore Filter Design on a Budget
Application Report SLOA096 December 2001 More Filter Design on a Budget Bruce Carter High Performance Linear Products ABSTRACT This document describes filter design from the standpoint of cost. Filter
More informationLM5001 High Voltage Switch Mode Regulator
High Voltage Switch Mode Regulator General Description The LM5001 high voltage switch mode regulator features all of the functions necessary to implement efficient high voltage Boost, Flyback, SEPIC and
More informationLM118/LM218/LM318 Operational Amplifiers
LM118/LM218/LM318 Operational Amplifiers General Description The LM118 series are precision high speed operational amplifiers designed for applications requiring wide bandwidth and high slew rate. They
More informationApplication Note AN- 1118
Application Note AN- 111 IR331x : urrent Sensing High Side Switch P3 By David Jacquinod Table of ontents Page Introduction... 2 Inner Architecture... 2 Reverse Battery Protection... 2 Wait function...
More informationAPPLICATION NOTE AP050830
APPLICATION NOTE AP050830 Selection and use of Ultrasonic Ceramic Transducers Pro-Wave Electronics Corp. E-mail: sales@pro-wave.com.tw URL: http://www.prowave.com.tw The purpose of this application note
More informationSINGLE-SUPPLY OPERATION OF OPERATIONAL AMPLIFIERS
SINGLE-SUPPLY OPERATION OF OPERATIONAL AMPLIFIERS One of the most common applications questions on operational amplifiers concerns operation from a single supply voltage. Can the model OPAxyz be operated
More informationConsiderations When Specifying a DC Power Supply
Programming Circuit White Paper Considerations When Specifying a DC Power Supply By Bill Martin, Sales/Applications Engineer Every automated test system that tests electronic circuit boards, modules or
More informationΣ _. Feedback Amplifiers: One and Two Pole cases. Negative Feedback:
Feedback Amplifiers: One and Two Pole cases Negative Feedback: Σ _ a f There must be 180 o phase shift somewhere in the loop. This is often provided by an inverting amplifier or by use of a differential
More informationLD7550-B. Green-Mode PWM Controller. General Description. Features. Applications. Typical Application. REV: 01a 12/22/2006 LD7550-B
12/22/2006 REV: 01a Green-Mode PWM Controller General Description The LD7550-B is a low cost, low startup current, current mode PWM controller with green-mode power-saving operation. The integrated functions
More informationTransistor Characteristics and Single Transistor Amplifier Sept. 8, 1997
Physics 623 Transistor Characteristics and Single Transistor Amplifier Sept. 8, 1997 1 Purpose To measure and understand the common emitter transistor characteristic curves. To use the base current gain
More informationMP2365 3A, 28V, 1.4MHz Step-Down Converter
The Future of Analog IC Technology MP365 3A, 8,.MHz Step-Down Converter DESCRIPTION The MP365 is a.mhz step-down regulator with a built-in Power MOSFET. It achieves 3A continuous output current over a
More informationPreliminary Datasheet
Features Macroblock Preliminary Datasheet 1.2A Constant Output Current 93% Efficiency @ input voltage 13V, 350mA, 9~36V Input Voltage Range Hysteretic PFM Improves Efficiency at Light Loads Settable Output
More informationFrequency Response of Filters
School of Engineering Department of Electrical and Computer Engineering 332:224 Principles of Electrical Engineering II Laboratory Experiment 2 Frequency Response of Filters 1 Introduction Objectives To
More informationDigital to Analog Converter. Raghu Tumati
Digital to Analog Converter Raghu Tumati May 11, 2006 Contents 1) Introduction............................... 3 2) DAC types................................... 4 3) DAC Presented.............................
More informationELECTRONIC POWER SYSTEMS
ELECTRONIC POWER SYSTEMS TRADEOFFS BETWEEN SINGLE-PHASE & THREE-PHASE POWER WHITE PAPER: TW0057 1 Executive Summary Modern Electronic Systems are quite often powered from a three-phase power source. While
More informationWelcome to this presentation on Switch Mode Drivers, part of OSRAM Opto Semiconductors LED Fundamentals series. In this presentation we will look at:
Welcome to this presentation on Switch Mode Drivers, part of OSRAM Opto Semiconductors LED Fundamentals series. In this presentation we will look at: How switch mode drivers work, switch mode driver topologies,
More informationTransformerless UPS systems and the 9900 By: John Steele, EIT Engineering Manager
Transformerless UPS systems and the 9900 By: John Steele, EIT Engineering Manager Introduction There is a growing trend in the UPS industry to create a highly efficient, more lightweight and smaller UPS
More informationPIEZO FILTERS INTRODUCTION
For more than two decades, ceramic filter technology has been instrumental in the proliferation of solid state electronics. A view of the future reveals that even greater expectations will be placed on
More informationTamura Closed Loop Hall Effect Current Sensors
Tamura Closed Loop Hall Effect Current Sensors AC, DC, & Complex Currents Galvanic Isolation Fast Response Wide Frequency Bandwidth Quality & Reliability RoHs Compliance Closed Loop Hall Effect Sensors
More information