Pspice To Ltspice Converter Weight
SPICEleft.htmleft.htmleft.htmleft.htmLast modified:December 20 19I have well progressed with mynext book on small-signal modeling of switching converters. I'vefinished four chapters and determined indetails transfer functions of the buck, the boost and theboost-converters (and their isolated derivatives) using the PWM switch model infixed switching frequency, fixed on- and off-time, quasi-resonant, voltage- andcurrent-mode control, CCM and DCM. Quite a nambitious project I now reckon but reviewers encouragements push me topursue the task. I will write the 5th and last chapter now and hope to submit the final manuscriptend of Q1 2020. The end of the year is approaching: bestwishes for 2020 to my reader friends world-wide!My most recent book describes how to applyf ast a nalytical circuits t echniques (FACTs) when determining linear circuit transfer functionsandis available from Wiley via numerous distributors. You will learn how to analyze simple to complex linear circuits by determiningthe circuit's time constants in different configurations. The idea is to split acomplex circuit into small sketches and solve them independently.
Then assemblethe results to form the complete transfer function. The book is published by Wileyin the IEEE press imprint. Each chapter is offering 10 fully-documentedproblems so that you can check if you have acquired the skill. This book iscurrently being translated into French and should soon be available in thatlanguage. If you have contacts for publications in German, Italian or Spanish, Iam open to suggestions.
The French version has now been released whilethe Chinese version is on its way.The front cover is shown below:There are 5 chapters, gradually introducing you to thetechnique. The Table of Contents (TOC) is.Chapter 1: it is an introduction with generalities ontime constants and transfer functions. You will learn how to determine theresistance driving a capacitor or an inductor by looking into the component'sterminals. Through a refresh on classical theorems, you will see how you cansimplify circuits analysis and smoothly enter the world of Fast AnalyticalCircuits Techniques (FACTs).Chapter 2: this chapter starts with the definition ofa linear system.
What are the mathematical differences between a linear and anon-linear circuit. Time constants are introduced and linked to the forced andnatural responses of a circuit in the time domain.
Transfer functions areformely defined with various polynomial forms up to the order n. The 1st-ordergeneralized tranfer function is given in this chapter.Chapter 3: the Extra-Element Theorem (EET) is definedthe way I understood it, with many simple drawings to teach how it was derivedby Dr. Null double injection is explained in this chapter with amethod to verify your calculations using SPICE. Numerous simple passive andactive circuits examples follow to show the power of this theorem. A simplevariation of the theorem leads to the generalized transfer function of a 1st-ordersystem, identical to that given in Chap.
2 but following a different path.Using this generalized form, you do not need to go through the null doubleinjection and it amazingly simplifies the determination of transfer functionsfor any 1st-order networks.Chapter 4: this chapter is entirely dedicated to passiveor active 2nd-order circuits, built with op amps or transistors. The 2-EET isdefined and a simple method is detailed to obtain transfer functions swiftly.Once the skill is acquired, you can determine some of the transfer functionswithout writing a single line of algebra!Chapter 5: we enter 3rd-order circuits and above,using a generalized transfer function formula. Learn how you can determine op-ampbased filters transfer functions by calculating time constants in variousconfigurations. By breaking a complex circuit into smaller and simplerconfigurations, you can determine the transfer function of a complex circuitefficiently. By using SPICE in each step, you can verify your results andcorrect a mistake at any time in the derivation.Google books offers a preview.
There is a book reviewand PET published an excerpt.alsopublished another review in the July 2016. The September 2016 IEEE newsletter has published a product.Each chapter ends with 10 fully documented examples/problems.All corresponding Mathcad files are available. I maintain a list ofidentified typos.There are more than 70 fully solved examples of transferfunctions from 1st to 4th order, active and passive.
The complete list is.The book is announced on these sites. For IEEE members, a 35%discount is available. Information.(France) (UK)(Germany)(US)(Japan)(Italy)(UK)The French version has arrived!
La version franc aise estarrivee etest disponible chez Dunod depuis mars 2017. Voicidu livrede crivant son contenu.distribue le livre.-Switch-Mode Power Supplies: SPICE Simulations and Practical Designs,second editionis now completed and the book has beensent to the printer. It took me a while to clean all typos, errors and baddrawings that you, readers friends, have been kind enough to report. The finallisting for the 1st edition is posted.
So,what do we have in this second edition? Well, some chapters have been expanded,some simply cleaned up. Here we go for the detailed list:Chapter 1: the complete derivation of all rms currentsin CCM or in DCM for the power switch, the inductor, the diode and theinput/output capacitors is now fully documented.
All formulas have been testedand several Mathcad files will be available on the editor site to let youcalculate these data depending on your design. Not only rms currents arecalculated, but also the various time durations in DCM for instance. Convenienttables summarize constraints at the end of each subsection.Chapter 2: on top of the classical PWM gain derivation,a feedforward small-signal block has now been described. The complete small-signalmodel of the PWM switch operated in current mode has been added and simulated.Duty ratio factories have been described to show how you can get the ac responseof a DCM or a CCM current mode converter with a voltage-mode model by adding asingle in-line equation to the existing model. Sub-harmonic instabilities arenot predicted but low-frequency response for both modes perfectly agrees withthat of higher order models. For those interested in small-signal modeling, Iadded an appendix in which I derive the ac response of a voltage-mode boostconverter operated in DCM. You will see that despite previous SSA prediction,DCM converters are still second-order systems whose quality factor is simplymuch lower than in CCM.Chapter 3: the compensator section has been expandedwith OTA transfer functions for type 1 and 2.
A complete TL431 bipolar-basedmodel has now been included in this new editionChapter 4: some new SPICE blocks have been describedand in particular, a corrected D flip-flop which is now more robust to forbiddeninput states.Chapter 5: clean-up of the existing section mainlyChapter 6: I have included a complete small-signalanalysis of a BCM PFC stage when operated in current or voltage mode control. Ialso added a section letting you predict what the bulk minimum voltage will bewhen you have selected a normalized capacitor. This is important to know thisbulk valley voltage as the converter will have to pass 100% of the power whilein this input range.Chapter 7: this chapter now includes a completeexplanation of the over power phenomenon in flyback converters operated in CCM,DCM or in quasi-resonance (QR). Over power protection or OPP, is an importantpart of the flyback design. It is there to compensate the extra output power (hencecurrent) a flyback converter will deliver when supplied from its highest inputvoltage.
If no precautions are taken, risks of fire or destruction exist. Thisnew section explains the origin of this output power runaway and how tocompensate it.
Small-signal has not been left aside and a small-signal model ofthe QR flyback converter in current mode is presented. A section showing how toaccount for the nonlinear variation of the Coss capacitor has been added as wellas a simple laboratory circuit to check for transformer saturation.Chapter 8: the complete transfer function of theactive clamp forward converter operated in voltage mode has been added with stepby step derivation as well as tests a against prototype response. Compensationdetails for a 30-A dc-dc are also offered. The coupled inductor small-signalresponse has also been revamped thanks to comments from a sharp reader.There is no CDROM in this new edition, most of the files willnow be available on line from the McGraw-Hill site. These files, together with achapter sample are available through the dedicated landing page.Mr. Jean-Marie Merienne has kindly translated the book'sMathcad files from version 15 to Mathcad Prime.
You can download theversions and theworking.The book distributors(France)(US)(Canada)(Japan)(Germany)(UK)(China)(China)Comments, feedback and corrections: I keep a correction filein which I compile your findings and comments. The file isand will be updated when needed.Designing Control Loops for Linear andSwitching Power Supplies: a Tutorial Guide is now available forsale. This new book took me three years of work, every night. It first startedin 2009, I wanted to write an exhaustive text on how to design compensators forpower supplies. Operational amplifiers (op amps) were first on the list, but I thenrealized that there was many other types of active elements that could be used toperform this function: TL431,operational transconductance amplifiers (OTA) and shunt regulators like in theTOPSwitch (Power Integrations) series. If literature abounds on op amps, there are few documents onTL431, OTAs and TOPSwitches, but all scattered in application notes sometimesdifficult to find.
Ihave dedicated an entire chapter for each of them, even detailing TL431internals. Of course, there are non-isolated and isolated versions with anoptocoupler.Please check theindifferent languages (English, French, German, Japanese, Mandarin, SimplifiedChinese, Korean and Spanish). Thanks to all my friends world-wide for their kindhelp! (Bernie, Werner, Ken-san, Kelvin, Patrick, W.S. And Juanito)You can download the Table of Content.The book starts to explain loop control theory in a verybasic approach, 'with the hands' as we say in French.
Then, the followingchapters go deeper into the theory you need to know as a power supply engineer.There is some mathematical content but there are a lot of examples that show howto put the theory at work. This is a strength of the book to my opinion: itbridges theory that you have learned at school with what you will face in yourengineering challenges. For instance, we all learned how to build a compensatorwith an op amp (I still have my class documents) but how do you apply thatknowledge to a TL431, a Transconductance Amplifier or a Shunt Regulator?
Andwhat if you add an optocoupler? Throughout the pages, you will learn where phasemargin comes from, how to select crossover frequency, how to efficientlycompensate a control system and much more! I hope you will enjoy this new workthat took me 3 years to write. As usual, almost all the equations were derivedby myself with all the steps so that you can follow.and correct me if I amwrong!Chapter 1:t hischapter is an incomplete introduction to control systems. I have tried to gatherthe very basic things you need to know about control systems and I introducedsome of the tools you will need in the following chapters. This chapter is forpeople who have no notion of control systems at all and want to understand howsuch a system works.
No complex diagrams or difficult equations, a step-by-stepintroduction. Of course, experts reading this chapter will smile but, again,this brief introduction is not for them, they can jump to chapter 2 immediately: ) Please note that the entire Chapter 1 is offered for download by Artech onits.Chapter 2:now we start the discussion about serious stuff. I am showing how to properlywrite transfer functions. You will discover that a transfer function can bederived in different ways. One of them uses brute-force algebra.
The result isanalytically correct but when you look at the result, it is almost impossible tosay if there is gain,if there are poles and zeros and where they are hide. Re-write the samefunction the proper way and all these information clearly appear in the equation.
Knowing how to write transfer functions this way isthe key to fastanalytical techniques and so-called low-entropy expressions. Learn how to getthe poles and zeros just by looking at the electrical schematic!Chapter 3: in this chapter, Iexplain where phase and gain margins come from. At school, I was told that'you need to have at least 45 of phase margin at crossover' and that was it!
Inever had a clue where this number was coming from and how to apply it. Learnhow phase margin is linked to the quality factor of a second-order system.
Pspice To Ltspice Converter Weight Guide
Checkhow to read these data on Bode but also on Nyquist plots. Learn what modulus anddelay margins are. Understand the importance of output impedance and the way toshape it via the right crossover frequency.Chapter 4:we now enter the world of compensation: how to shape the return path so that mycontrol system be stable, fast and precise. PID configuration are explored and Ireveal the link between coefficients and poles/zeros placement.
Nothing new here,but this is done step by step so that you can follow the path. A few examplesput the PID at work and show that in some cases where Bode says it will bestable, the system isn't. Learn why and how to properly compensate your product.Chapter 5:this chapter covers compensators using operational amplifiers. You will findtype 1, 2 and 3 structures, with and without optocouplers. You have all theequations, ready to use. I even re-wrote the k factor equations for thoseinterested in the approach. All derivations steps are detailed and commented.C hapter 6:transconductance amplifiers (OTAs) are popular among the IC designers community.They are easy to design and require less die area than they op amp cousins.However, the set of equations you have for op amps does not readily apply.
I havere-derived all the design equations in this chapter. Even if you add anoptocoupler, it is covered. Also, I explain why it is difficult to build a type3 with an OTA and what are its limitations.C hapter 7:the TL431 is the most popular elements found in todays power converters. Hostinga precise reference voltage and an open-collector op amp, it is a remarkablywell-crafted device.
Actually, op amp and reference make only one and thetransistors arrangement was made by a genius designer! Check TL431internals and learn how to use that component to build type 1, 2 and 3compensators with an optocoupler.Chapter 8:TOPSwitches from Power Integrations are very popular high-voltage switchers.Rather than hosting a voltage control input, these devices are sensitive toinjected current as a means to control the duty ratio. Again, previous equationsno longer fit and I have reworked them all for the classical compensator types.Chapter 9:bench measurements are mandatory when you deal with control systems. It isimportant to verify that all hypothesis you made during the design phase lead tothe expected phase and gain margins on the real prototype. And a prototype is areal piece of hardware, not a Simplis simulation bench, please! In this chapter,I explain the theory behind closed-loop measurements and where to be careful forreliable measurements.
Then follow 5 design examples, putting theory at work.Simulationfiles:There is no CDROM with that book but there are availablethatcorrespond to some of the book examples. These examples are simulated withIsSpice and their demonstrationversion will certainly run a few of them. Didier Balocco was kind enough totranslate some of these examples in. These arebeta versions. If you have the time to translate the remaining examples, I willbe glad to post them in this webpage.FeedbackYes, I know it for fact, there will be errors and typos inthe 1500 equations I derived in this book. The term derived is correct because Ireally worked almost all these equations myself. First, because doing so let meidentify obstacles that I could teach you how to avoid them when you follow my steps.Second, copy/pasting equations or pulling them out of thin air is not my writingstyle as an engineer.
I apologize in advance if you find errors, mistakes ortypos in these mathematical expressions. Given their number and despite the careI put in chasing them, this is unavoidable.Please, let me know where these errors are and I will maintain an errata list (,),giving credits to people who found these mistakes. Merci d'avance! (Thanks inadvance).The book distributors:(France)(US)(US)(Canada)(Japan)(Germany)(UK)(China)Artech Houseoffers a coupon to let you order the book from them directly with a 20% discountand free shipping! The flyer is.-If you want to read my interview by EEWeb, please follow this.
I'm suresome of you will recognize the guy in the wall poster: )-Switch-Mode Power Supplies: SPICE Simulations and Practical Designswas released in 2008. Another book on power electronics you say? In the technicalliterature, you either have books that are purely academicals and offer in-depth analysis of converters, unfortunately without the essential linksto the market reality. You also have purely practical books that pull equations out ofthin air without any theoretical grounds. This book bridges both approaches andwill hopefully please the power electronics student and the design engineer, bothlooking for analytical explanations but also for practical solutions when facingcustomer demands. This book is really about power supplies designs, with SPICEas a design companion. It covers dc-dc but also ac-dc converters.
By the way,the ac-dc conversion in offline converters is made by the diodes bridge and thecapacitor, the downstream converter is always a dc-dc, isn't it?in French, English, German,Mandarin and Japanese!!(Xie -xie to Patrick Wang and arigatogozaimasu to Iguchi-san!)The book is now available in simplified Chinese and Korean. Thank you toMr Zhangde Lu who translated the whole book in a record time! Mr Lu is ateacher in Shaoxing university in China. The book is available fromand Chinese links are posted below.The book is organized in eight chapters covering the followingsubjects:Chapter 1: this chapter starts with the basics ofdc-dc conversion, step by step with linear regulators used to deriveessential formulas such as closed-loop impedances or closed-loop inputrejection. Then the classical buck, boost, buck-boost are analyzed in CCM/DCMand critical modes until an input filter is added. There, you will discover the effectsof the filter insertion and learn how to compensate the converter while still attenuating theinput noise (95 pages).Chapter 2: small-signal modeling is really animportant topic if you want to be serious about power supply designs. Thechapter starts by showing what State Space Averaging is all about and howcomplicated it can be.
Then, the PWM switch model is introduced and three newversions are derived: auto-toggling DCM/CCM voltage-mode and current-modemodels, with sub harmonic prediction in CCM for the later. Of course, thesemodels are large-signal ones and operate in dc, ac and transient analysis.Finally, a borderline model is derived, later used in PFC stages. This 100-pagechapter really explains how these models were derived and how to use them foryour studies (146 pages).Chapter 3: loop control is always hard to understandfor some new comers. I've strived to make things look simple, explaining how thek factor was derived and showing that, sometimes, it is not a panacea. I propose different equations to let you manually select the poles and zeros, crossing over at theexact desired frequency. Also, in most of the books, only opamps are used to illustrate compensation.
In this book, I derived the transferfunctions of TL431-based type 2 and 3 compensators and I showed how the optocouplerpole can affect the phase margin (100 pages).Chapter 4: this is where you will learn how to buildyour basic subcircuit blocks and how to construct your new models, if necessary.For instance, how to model the error amp of the UC384X family. Understand thedifferences between syntaxes and learn how to write in-line equations. A sectionspecifically details the derivation of a magnetic model, based on non-linearjunctions. See how to wire generic PWM models in various configurations for thebest simulation speed. Learn howto extract physical data from a transformer to later pass them to a subcircuit(66 pages).Chapter 5: in this chapter, we cover the design ofdc-dc converters, the classical structures, in both voltage-mode and currentmode configurations. There are small-signal analysis and transient studies inall cases The front-end filter section is also analyzed with input ripplespecification targets (84 pages).C hapter 6: rectifying the sinusoidal mains is asection common to all ac-dc converters.
After all, the diode bridge and thecapacitor are the elements that really perform the ac to dc conversion. Thedownstream converter is still a dc-dc, no? This chapter covers the classicaldiode bridge configuration then further introduces passive power factor correction, quicklyfollowed by active power factor correction. The most popular topologies arecovered and there are several design examples. An extensive usage of the averagemodels is made here, leading to extremely short simulation times (88 pages).C hapter 7: it is time to describe the isolatedbuck-boost also called the flyback converter.
This chapter covers a lot oftechniques pertinent to the flyback converter, what is the leakage inductor role,how it affects the drain voltage excursion and how you can use its presence inactive clamp versions etc. The design section contains useful tricks to limitthe converter power capability at high line for instance or to compensate theleakage spike on the auxiliary winding. There are three design examples, among which amulti-output borderline converter using the new BCM average model, alsodescribed in the book (160 pages).Chapter 8: the forward converter is widely used in ATXpower supplies (the so-called silver box) where the 2-switch configurationexcels in 250 to 400-W applications. The chapter explores the various resetmethods and introduces you to multi-output configurations through mag amps, orsynchronous rectifiers. A complete design example is proposed at the end of thebook (129 pages).CDROM: the CDROM found with the book contains some ofthe most popular demonstration versions of currently available simulationsoftwares.
I strived to give away almost all the examples of the book in OrCAD/PSpiceand ICAPS/IsSpice formats. Some of the distributed versions also feature exampleskindly translated by the software editors themselves. This is the case for uCap,TINA, Multisim, B2 Spice, 5Spice. Other demos include Power 4-5-6, Transim andTopSpice. I updated the Excel file dedicated to the k-factor to whichTL431-based configurations have been added.Distributed libraries:I purposely created specific application circuits that arenot given away with the book. The library I am separately distributing includes the UC384X(UC3842/UC3843/UC3844/UC3845 SPICE models) preciselymodeled and implemented in a lot of application examples.
The same applies for Power FactorCorrection circuits, ready to go on several platforms. The library andapplication circuits are available in different formats that are Micro Cap, TINA,OrCAD and IsSpice. You can download an application listing to checkwhat is inside these libraries - also available for TINA and Micro Cap -or. Please drop me a line to my address:('SPICE library' as thesubject ) to learn about thispackage andhow to get it. I am currently setting up a distribution network for these files.I also have participated to the development of a morecomprehensive library file with AEi Systems.
There arecurrently more than 200 PWM IC models in this file and you can obtain a detailedquotation and information via this.So what?Yes, I know, there is place for more and there are subjectsthat I did not cover. However, this last book took me three years to finish andI felt I was writing a new never ending story.: ) I therefore keptinteresting stuff for a next edition, in a few years from now.
For instance, Iwill show where the phase margin value come from and how to analytically linkthe crossover frequency and the phase margin to the converter output impedance.FeedbackPlease, forgive me in advance in case you find errors,mistakes or typos, despite all the efforts in trapping them, there might stillbe some left, even further to thorough corrections ran by numerous reviewers. Ihave maintained a list of collected remarks, with credits to authors that havefound them! The corrections file for the first edition is, compiling all errors and mistakes previously published.ReviewsThe US IEEE Power Electronic Society has reviewed my book andpublished its comments in the PELS April.Afrom Design/Analysis Consultants, Inc. Wherethe book is recommended!An excerpt has been published online in.The book appears in the 'Best Power Supply Design Books'directory in SMPSTechDr. Yan-Fei Liu from Queen's University (Canada) published ain the Canadiansection of IEEE.The book was one of the best sales for technical booksat ISSCC Conference 2009. Read this.The book distributors:(France)(US)(Canada)(Japan)(Germany)(UK)(China)(China)(India)(India)(New-Zealand)(Australia)There are several reviews you can read in the Amazon USto learn about the book acceptance by engineers.Presentations and papers to download, C.
Basso:this document details how a forward converter can possibly deliver morepower at low line than in high-line conditions. Theassociated Mathcad 15 file is., C. Basso: this seminardescribes the modeling of buck converters operated in different controlschemes with the fourtransfer functionsof the CCM buckconverterpresented as examples.
SPICE,SIMPLIS and,finally, bench experiments are shown along the examples to confirm theorymatches reality. I have purposely built demonstration boards showinghow experimental results agreewell with the simulations if you properlycharacterize some of the components.The audience wasbetween 100-150 people and I was really happy to seeyou all again. Thank you for attending this session and see you next yearin New-Orleans!, C. Basso:this document is a quick introduction to the fast analytical circuits techniquesor FACTs and apply them to a DCM-operated SEPIC. It was published in the IEEEPower Electronics Magazine from September 2017., C. Basso: this seminardescribes how to obtain the control-to-output transfer function of a converterusing small-signal analysis, average model SPICE simulations, SIMPLIS and,finally, bench experiments. I have purposely built demonstration boards showinghow experimental results match well with the simulations if you properlycharacterize some of the components.
I used the FACTs to determine the transferfunction of the boost converter in voltage-mode control. The audience wasbetween 100-150 people (statistical data ) and I was really happy to seeyou all again. Thank you for attending this session and see you next year!, C. Basso:this document details how to derive the transfer function of the type 3compensator when the open-loop gain AOL is involved.
The Mathcad sheet is., C. Basso:this document shows how you can re-use the original voltage-mode PWM switchmodel and by adding a simple resonating capacitor, turn it into a current-modemodel able to predict sub-harmonic oscillations in CCM with dc and transientcapabilities.
It uses the models ported to LTSpice by Didier Balocco (seeseveral lines below for download) and builds on experiments kindly done by MarkDimattina. The LTSpice files are., C. Basso:this presentation focuses on interactions between an EMI filter and a switchingconverter. Fast Analytical Circuits Techniques are at work here and they trulysimplify the analysis. I was happy to see some known faces again and hope thenew ones enjoyed the show. 108 people were registered for this seminar. The seminar slidesareand the statistic.
Thank you all!, C. Basso:this Mathcad 15 file shows the impact of the op amp open-loop gain and its twolow- and high-frequency poles in a type 2 compensator. It is usually not aproblem for low crossover frequencies but as soon as you need gain and phaseboost at values at or beyond 10 kHz, the GBW product matters. The PDF is., C. Basso:this presentation introduces you to Fast Analytical Circuits Techniques whichlet you derive transfer functions in a quick manner and sometimes withoutwriting a single line of algebra. The method is at work with two switchingconverters, the buck and the buck-boost in voltage mode. The seminar went welland I thank you all in the audience!
Statistics of this seminar are., C. Basso:this paper studies the dynamic response of a current-mode flyback converteroperated in boundary mode and switching in different valleys., C. Basso:this 3-part article originally published indescribes how the leakage inductance affects the conversion ratio of a flybackconverter by truncating the duty ratio.
Power dissipation via the clampingnetwork also damps the control-to-output response as modeled through a newaverage circuit., C. Basso:this short PPT shows how you can wire the PWM switch model to simulate thecontrol-to-output response of a Zeta converter., C. Basso:this presentation capitalizes on what has been discussed during previousseminars and bridges theory with practical results. For instance, what is theimpact of an op amp slew-rate and GBW product on phase margin for instance? Howto ensure clean start-up sequences on isolated dc-dc converters? These are amongthe few topics I tackled during the session. Again, thank you all for attending!Statistics about this seminar are., C.
Basso:this seminar shows how to derive the control-to-output transfer function of theboost converter operated in peak current mode control., C. Basso:this short PPT shows the ac simulation results I was able to obtain with myvoltage-mode model to which a duty ratio factory was added. Results are not farfrom what Simplis predicts., C. Basso:this presentation shows how to independently model the control voltage Vc toduty ratio D block in a current mode converter.
The presentation shows that byusing a voltage mode stage to which a separately-modeled Vc-to-D is added, youobtain the complete control-to-output transfer function of the CCM CM buckconverter., C. Basso:this presentation shows the PWM switch models at work in various converterstructures. Fixed switching frequency in voltage and current mode is describedbut borderline conduction mode is also demonstrated. This presentation alsointroduces the small-signal model of the active clamp forward converter operatedin voltage mode control.
The model is then compared to bench measurements. Theaudience peaked to 150 people during the show, thank you all for attending!Statistics are., C. Basso:I have been teaching and speaking in front of an audience for a while now. Myfirst speech, which goes back 20 years, was a complete disaster: trembling voice,shaky legs and so on. I made the obvious mistakes untrained people do and withtime, I started to improve by learning from professionals. I also took severalpresentation skills classes (training was excellent) and I improved over years.
Pspice To Ltspice Converter Weight Table
At least I hope I did: ) Forthose who need to present, I compiled most of the mistakes you must avoid to makeyour speech efficient and credible. I have one inas well., C. Basso:this presentation teaches you how to derive the transfer function of a flybackconverter operated in constant peak current while switching frequency iscontrolled. This technique is now widely used in converters implementingfrequency foldback in light-load conditions., C.
Basso:this presentation teaches step by step how to derive large and small-signalmodels of switching converters. The presentation starts by showing how tolinearize non-linear equations and then describes models for voltage-mode andcurrent-mode CCM/DCM converters. It extensively makes usage of the PWM switchmodel. A model of a QR flyback model is also presented. Merci to my friend ChrisWarin for kindly taking the below pictures!Introduction by Mrs Chen, chairman of the conferenceAgenda of what I am about to presentThere we go, the audience peaked to 200 people which is very rewarding, thankyou all!, C. Basso:this short document shows you that a real type 2 built with a TL431 andinvolving two lanes is not wired as a type 2 with an op amp: a single capacitoris enough across the TL431.
Ltspice Models
Adding an extra RC is useless., C. Basso:this presentation teaches you some less known aspects of loop control theoryapplied to switching and linear converters.Things like delay margins, modulus margin or how a PID converts to a type 3compensator.
They were in this new seminar entitled 'TheDark Side of Loop Control Theory'. The seminar statistics are.This is me, together with Franki Poon from the PowerEsimwebsite!, C. Basso:this presentation teaches you the untaught aspects of the flyback converter.Things like Over Power Protection (OPP) or Quasi-Resonant small-signalcompensation are rarely included in seminars. They were in this one, entitled 'TheDark Side of Flyback Converters'.These are the covered subjects in the 3-hour time. The RHPZpresence in both CCM and DCM was explained to the students., C.
Basso:this paper updates the current book content by improving the formulas used toderive the bulk capacitor value in a front-end rectifying section. Nothingspectacular here but I realized that these results could help the designcommunity to calculate the right value., C.
Basso:this presentation teaches you how to design compensators based on TL431, op ampsor OTAs. This seminar associated with that of 2009 represent the subject of mynew book on loop control.This is me, teaching how to derive the full analysisequations for a type 2 compensator with an op amp. There were more than 100students in the room., C. Basso:this document shows how I built an auto-toggling average model for the phaseshifted converter.
The model exists in IsSpice but also in PSpice. Both averageand generic cycle-by-cycle models are available in ready-to-use templatesdescribing a 12-V/25-A power converter. They are part of the distributed libraryfiles., C. Basso:this presentation teaches you where phase margin and crossover frequency comefrom and guides through the stabilization process of a dc-dc converter.I am on the left, on the ON Semiconductor booth at APEC 2009.The other fellow is my friend Larry Jenck.s, C. Basso:this is an article I wrote in 2009 that describes how an optocoupler works andwhy you should always characterize its inherent pole. A method is offered toextract it quickly through a simple test fixture., C. Basso:the TL431 is never studied as a part of the compensator in control theorybooks.
However, this is a market reality, op amps are rarely used! Gothrough this new series of articles and learn how the TL431 works and how youcan use it in a variety of configurations., C. Basso:this paper teaches how the cross-over frequency affects the output impedance ofthe converter you want to stabilize., C.
Basso:this paper explains the relationship between the open-loop phase margin youselect and the resulting transient response you can obtain., C. Basso:this paper shows how to get the small-signal model of a flyback converteroperated in the so-called quasi-resonant mode., C. Basso: the Right-Half-Plane-Zero plagues theflyback or the boost converters operated in CCM. This paper explores the originsof the RHPZ., S.
Basso: aTL431 combines a fast and a slow lane. How to measure the total loop gaincombining both lanes is the object of this paper.' ': this document was presented in PCIM 2005and covers the history of SPICE models.: this is the paper published in the PCIMproceedings., PCIM 2003: this model usesCoPEC approach to model a QR controller. There are two associated models, inand.: a short PowerPoint which shows howmy new models match calculations in both VM and CM for a forward converter.New models to download: MarkDimattina offers a way to implement the PWM CM version in LTspice. Thank you forsharing your models Mark.
The documentation is.:Byron Rogers kindly shares his PWM Switch model also intended to be simulated inLTspice.: an interesting discussion on the TL431 and theperformance of several available models.: Didier Balocco has come up with a new series of LTspice circuits implementing the PWM Switch model in voltage and current modes.There are plenty of examples plus a quick installation guide. The files are. Merci Didier!: Charles Denton has been kind enough totranslate the PWM switch models in LTspice. Yes, it is obvious, you need a good book to understand how to usethem.;-)It has been reported that parameter 'K' could be mixed byLTspice with the Boltzman constant. To avoid this, please change 'K' into 'Kf'and it should work. Kindly pointed out by Dennis in March 2015.: the PWM switch model working inVerilogA, nicely translated by Nico Cyr from ON Semi.: the PWM switch model working inVerilogA, a new model contributed by Rainer Krenzke from Dialog Semiconductor.: this is a new automatedsoftware which calculates the TL431 elements to stabilize of a flyback converteroperated in peak current mode control. The software includes mode transition,sub harmonic poles and optocoupler pole contribution.
Check it out!Switch Mode Power Supply Cookbook -download filesSam Ben-Yaakov models are based on the Switched Inductor Model (SIM) conceptas described by many publications at:.The models offered are averaged models adapted in a.SUBCKT form and let you simulate thefollowing topologies: BUCK, BOOST, BUCK-BOOST/FLYBACK, FORWARD, SEPIC in both Current-Mode(CM) and Voltage-Mode (VM) versions. As averaged models, they find theirdc point aloneand allow AC and TRANsient simulations. Please note that CM models do not predictsubharmonic oscillations at Fsw/2 (,).Ridley models are ac models only(,). They can't compute theirdc point alone and are therefore dedicated toac simulation s only. They correspond to an adaptationof original SPICE2 scripts where complex parameters needed to be calculated by the user.These models naturally shield you against these drawbacks and let you simulate the sametopologies as above in a snap-shot.
They nicely predict F sw/2oscillations.presentedduring PCIM 2001 some extensions to his original GSIM models. These newmodels now include various losses such as inductor ohmic losses, switchr DS( on), diode forward drop and dynamic resistance. These devices have beenencapsulated into working subcircuits (current-mode and voltage-mode) andare available for bothand.and Dragan Maksimovic, from,have included a simulation portion in the latest edition of their book,'Fundamentals of Power Electronics'. These models were firstpresented during PESC 1999. I have adapted CCM-DCM1 and CCM-DCM2 to IsSpice4because original versions were only PSpice compatible.
Hello everybody, i have figured out that LTspice uses a different model description when compared with Texas Instruments opamps.I would like to simulate the TLV271.I downloaded the model from the TI website and created a new symbol called TLV271. I made sure it points to a TLV271.lib. Changed the name of the subckt to make it work. I can simulate without any errors, but the values are all wrong. Output rises to 2400Volts.When comparing an opamp subckt such as the LT1490 in the LTC.lib, i noticed that LT uses a far more advanced model description.
Using google, i found there are model 1 and model 2, spice model descriptions. The TLV271.lib is a model 1 according to the comments in the TLV271 file. I can assume, that LT uses for the LT1490 the model 2 Spice model description.My question is:Are there any functioning TLV271 models out there for LTspice? It is not really an issue, but i just use the TLV271 often and it works fine.
Would be fun to play with while using LTspice. I do not want to use TI swcad.
I like LTspice more. Well, i asked someone who knows more than me about spice simulating on my work today and he gave a very likely explanation:There are multiple ways to model behavior of a component.An opamp can be modeled exactly as a component with lots of resistors and capacitors and lots of transistors.
A true accurate model based on the actual inner workings of the opamp. But slow to simulate.But it is also very common to model a certain component with transconductance descriptions.For example, multiple voltage dependent current sources (or voltage dependent voltage sources)may be used that expect input on the non inverting input and the inverting input.Modeling behavior of an opamp but not with full accuracy. It does make the spice modeling a lot faster. But can also allow why the output in the simulation can rise to up to 2400 Volts while using a 10V positive rail.He suspected that this is the case with the TLV271 spice model.It will probably work, but the way i used it allowed for strange results.I will have to do some testing to be sure.Opamp fundamentals.
I would like to officially state that today i labeled myself as an idiot and i bow my head in shame.:$I found the error i made. The TLV271 is not the problem. It was in my circuit.I have build the design from scratch again and it worked.After that, i started to trace back all the components from the original circuit that did not work and found an error in a label used to connect various parts of the circuit to the voltage rail. Mainly the TLV271 did not receive any voltage on its V+ pin.Funny thing is that when building a circuit, that is the first thing i measure before testing. Checking if all the voltage rails are connected and everything receives power. After that i start to test the circuit. But when simulating, i assumed the program would give an error if pins are not connected.
But it really is a good simulator, it does not provide warnings for wrong connected circuits.:$I think i need a vacation.In the end, i can still say i learned something.Because i now know how to make my own libraries with non LT components.I have now a little understanding of the spice modeling description.And i now know that LT spice will not always warn about errors in the circuit.It will just calculate while producing results with errors.In all honesty, i know the circuit works before even simulating, but sometimes it is just nice to do it. And it makes for easy screenshots to add in a document. To add with measurement screenshots taken with the oscilloscope on the actual physical circuit.And my beloved TLV271, i can use it in my simulation.:wub:In the end, everything is always great.
LTspice sure works great, i just added a component from analog devices.The AD8211 current shunt monitor. ^^A short example coarse about how to measure current with an MCU:The AD8211 is great when used with a resistor with a value that is (with a little imagination) a power of 2. For example, 0.16 Ohms.The AD8211 has an amplification of 20V/V. This means that it will amplify the voltage difference between the input pins with 20.
20 is with a little imagination also a power of 2.Thus we can say the output voltage = 0.16.20.I.If we would convert this to a digital value with an ADC, we have an ADC count. Now, why do i keep mentioning that power of 2.Well, when the AD value is normalized and scaled because the MCU is a 32 bit (or a 16 bit) MCU, it is easy to normalize the value and scale it. Meaning multiply it by 100 or 1000. A 32 bit register can hold values signed from -2.10^9 to 2.10^9.0.16 will become 16 when properly done and 20 will become 2 when properly done.
Since i am kind of a perfectionist, i did not like the for me only limitation the AD8211 has. It would be nice to be able to measure as low as possible. Preferably a resolution of 1 mA would do fine for an indication. But the output would not go lower then 0.05 Volt or in worst case not lower then 0.1 Volt.And i do not want to switch between shunt resistors.
That is a serious issue.It really is a nice IC.The common mode input range exceeds ground level (-2V)and up to 65 Volt.Since i am connecting the shunt resistor with this ic before the regulator series pass element, it always receives a steady voltage.The output swings form 0.05 V (0.1 V worst case) to 4.95 V.The maximum voltage difference between the inputs must be 250mV. Since i use a resistor of 0.16 Ohm and a maximum current of 1A, i have 160mV. Well within specification.But i have to solve the issue of the output not going lower then 0.1 V worst case with a design trick. I have to circumvent it with using creativity. I must come up with an idea, test it and see if it works and meet all specified criteria.
Another way is to change the reference levels of the ADC.An Analog to digital converter has a reference. A SAR ADC for example has a low reference level and a high reference level. The low reference level usually represents the lowest value the ADC can measure and convert for value 0, meaning all bits are set to 0. With the used 10 bit ADC this would also mean all bits are set to logic 0. The high reference level usually represents the highest value the ADC can measure and convert as all bits set to logic 1. The value 1023 with a 10 bit adc.
Unfortunately, often when we do this we sacrifice i/o pins when an ADC is used integrated inside a MCU. We also sacrifice some measurement range.Often it is also not possible to change the reference low input (fixed to ground level) but it is often possible to change the reference high level.The third way is also a way.
What if i would not connect the GND pin of the AD8211 to ground level.But to a negative voltage rail. I do not need much, -0.1V is enough for worst case scenario. What happens is that we shift the lowest level of the output towards ground by shifting the GND pin to -0.1Volt.
The output level will not drop, and since we only need an output level of 3.3 V maximum there is enough freedom since the output voltage level of the AD8211 can go up to 4.95V.But we still need to use this with the current load from the first example to create an offset current to let a minimum current flow to compensate for the 0.1 V. The advantage is that we have more range with the ADC. Because with proper offset current adding, 0V means 0mA towards the output.I will just use the current offset subtraction trick.From the above example in the other post:Rshunt = 0.16 Ohm. 20. 1mA = 3.2mV.
This means the output should rise3.2mV for every 1mA. At 3.2mV per mA (3,3V/1023), and 3,3 V being 1023 means i have 1023mA full scale for a 10bit ADC. But i also need a little calibration space to compensate for offset errors of the ADC and the circuit.That 23mA i need to create an offset. I want to measure 1A full scale.But if the AD8211 output voltage level can not go lower then 0.1V, i have a problem. Because i have in the most optimistic scenario, 23.3.2mV = 73.6mV to create a range from 0mA to 1000mA measurement range.What will happen is that with 0.1 V, i will not reach 1000mA full scale, i will reach less. 0.1V/3.2mV = 31,25mA.
1023mA- 32mA (rounded figure) = 991 mA full scale. I have to hope for an AD8211 with an low output level of 0.05V. Then i have enough freedom to calibrate away by subtraction or addition any measurement error. Of course assuming that the entire circuit is linear from input to output.And the fun is that this all can be tested with LTspice too. Tomorrow i will have actually 3 ADC8211 in my possession to play with when i have the time.
I finally had the time to play with the AD8211. Created a small protopcb with resistor and decoupling capacitor. The AD8211 i used, came as low as 34mV with a 22000 Ohm load. Thus with a simple potentiometer i can create a small 20mA current offset to keep the output above the minimum voltage level.The LT1490 opamp is ideal to create a good linear power supply with a Nmosfet series pass element for regulation.
Advantage is that no negative power supply is needed to reach 0V. A small mcu driven step up boost circuit is all that is needed to provide the LT1490 with the necessary higher voltage to produce the needed gate source voltage for the nmosfet. The LT1490 functions up to 44Volts.Higher voltages need a design trick such as using the +V rail as the ground for the opamp (lifted power supply.)Nmosfets used for non switching audio applications are ideal to use for this purpose. For example the ALF08N16V.8A, 160V. When sleepy it is common to make an error.:The current through a resistor is voltage dependent.
Although the current sense resistor and the current offset circuit are placed before the series pass element, the voltage is still going to vary because of a varying load at the actual output. This will also vary the offset current when a resistor is used (I=U/R). And the offset current has to be a constant no matter what the actual output current is.Thus it is better to create a constant current sink. For example with an (good ol)LM317 from National Semiconductor (Now Texas Instruments), a potentiometer in series with a resistor(combined the 1.25V reference resistor) and a resistor acting as a load for the LM317. For a range of 10 mA to 30 mA it is easy to calculate. 1.25 / 0.01 = 125Ω and 1.25 / 0.03 = 42Ω.A resistor of 39Ω in series with a potentiometer of 100Ω will do.Gives us a range of 39 to 139 Ohm.
Will within spec.Supply voltage will be between 13V and 11V. The LM317 needs 3V minimum. We give it 5V minimum( Because of the 1.25V reference voltage. 0.75 above 3V minimum = experience).
Thus the worst case scenario is 11V - 5V = 6V for the load resistor from the offset circuit. We need to use the highest current to get the highest voltage drop over the load resistor (R=U/I).
6 / 0.03 = 200Ω. Round it up to 180 Ω(E12 range). In reality, 180. 0.03 = 5.4V. Thus the LM317 will have to withstand a little more.