Troubleshooting these circuits without a manual can be a real. Apr, 2016 how to repair a switching switch mode power supply. Repairing switched mode power supplies smps all about. A switch mode power supply is a type of electronic circuit used to convert power. In this ebook, you will learn all my advance troubleshooting and repairing secrets and you can become a professional in switch mode power supplies repair. More information on philips semiconductors components for powersaving smps systems, and power and battery. First the ac voltage will flow to a full wave rectifier bridge. Repairing switch mode power supplies brought to you by jestine yong. The working principle of switch mode power supply is different from the linear type. Getting into the power supply repair field is not hard. Download switched mode power supplies pdf 153p download free online book chm pdf. Jul 07, 2019 the filter circuit is used to regulate the output voltage of the switch mode power supply in order to get the pure constant dc voltage. Secrets on power supply repair and troubleshooting solving problems and failure in switch mode power supplies.
Secrets of smps repair and troubleshooting switch mode power supply smps repair sometimes can be easy and sometimes are quite difficult to solve the problem. Debugging powersupply startup issues texas instruments. On every occasion they have given us professional and efficient service in repairing our power supplies, thus enabling us to keep our customers equipment. Switched mode power supplies pdf 153p download book. Switched mode power supplies, often abbreviated to smps are considerably more complex than the linear regulated power supplies described in power supplies module 2. In some cases one may use a combination of switched mode and linear power supplies to gain some desired advantages of both the types. Smps design is separated into primary and secondary sections due to isolation topology. The principles of a switch mode power supply will be learned and can then be applied to choosing and design a supply. Understanding the functions of switch mode power supply troubleshooting linear power supply is extremely straightforward as opposed to smps or switch mode power supplies. Power supply repair processes have been developed to provide cost effective and efficient repair refurbishment solutions.
Ac voltage gets into the primary part in linear transformer after which modified the ac in a decreased or increased ac voltage with regards to the second transformer winding. Switch mode power supply repair, troubleshooting with dick. How switch mode power supply works smps troubleshooting. The primary section involves emi filtering, input rectification, and power factor correction pfc devices. The equations that describe the physics of switchers are deceptively simple. A ups, or a uninterruptible power supply, is a device used to ba ckup a power supply to prevent devices and systems from power supply problems, such as a power failure or lightning strikes. On semiconductor has been a key supplier of semiconductor products for switching power supplies since we introduced bipolar power transistors and rectifiers designed specifically for switching power supplies in. Tried contacting the manufacturer in the usa for a repair service but got no response, so we decided to source a local company and eventually found effect systems ltd, uk psu repair. How to repair a switch modepowersupply smps last updated on august 25, 2019 by swagatam 25 comments in this post we try to diagnose a burnt smps circuit and try to troubleshoot and repair the circuit. Understanding the functions of switch mode power supply. Secrets of smps repair and troubleshooting switch mode.
We recently received a switching power supply that failed in the field so we took the opportunity to do some troubleshooting and discuss the process here on. They are also known as switchingmode power supplies or smps for short. The power supply fault could be an open start up resistor only or could be even more than ten components burnt due to heavy lightning strike. Unfortunately, smps are a bit tricky to repair and i often get asked for advice. Switch mode power supply high voltage power supply high current power supply linear power supply dc power supply dc battery chargers if you need your power supply tested or repaired then give us a call at 369690110. Because they are more energy efficient than traditional power supplies, its rare to find any modern day electronics that dont utilize them. Nov 01, 2007 very often when i attempt to repair electronic devices, either mine or from friends, i find out the problem is with the power supply which these days is most often a switched mode power supply smps. Feb 06, 2011 switched mode power supply repair guide. Oct 02, 2014 switched mode power supplies have become ubiquitous in electronics as they provide precise voltages including high power with very high efficiency.
Switch mode power supply repair and troubleshooting with the help of dick smith flyback tester. Apr 06, 2010 a friend asked me to see if i could repair a couple of iota dls55 series m switchmode power supplies. For anybody still working on a desktop, look for the fan output in the central processing units cpu. An introduction to switchmode power supplies sep 27, 2007 abstract. These circuits offer distinct benefits and tradeoffs when compared to alternative methods of converting dc power. Technical explanation for uninterruptible power supplies upss introduction what is a uninterruptible power supply ups. Switch mode power supplies repair guide donwnload pdf ebook.
These definitions are widely accepted, but not uniformly adhered to. Technical explanation for uninterruptible power supplies. Introduction to switchedmode power supply smps circuits. Repairing switching mode power supplies audioxpress. Fortunately, its not difficult to fix pc power sup plies.
The main advantage of this added complexity is that switched mode operation gives regulated dc supplies that can deliver more power for a given size, cost and weight of power unit. Power is switch mode power supplies nxp semiconductors. Troubleshooting switched mode power supplies with a digital. Most of them are flyback, regulated, smps but not all. Power supply repair processes have been developed to provide cost effective and efficient repairrefurbishment solutions.
This is a great improvement over the amount of space previously required for power, freeing up space for more features to be included in the product being designed. Of all the circuits found in modern electronic equipment, the most common and easiest to troubleshoot is probably the switch mode power supply. Here is what you get from the switch mode power supplies repair guide. The latest spice simulation and design tools for creating stateoftheart switching power supplies fully updated to incorporate new spice features and capabilities, this practical guide explains, step by step, how to simulate, test, and improve switchmode power supply designs. Switch mode power supplies 271 pages, please visit. Troubleshooting switched mode power supplies with a. Switch mode power supply measurements application note. Mar 12, 20 uncover battletested switch mode power supply repair strategies by downloading this allinclusive smps troubleshooting manual thats stuffed with color photos.
Smps repair guide switch mode power supply repairing tips. You just received your assembled power supply printed circuit board. Switch mode power supplies daves tv service and repair. Mar 20, 2017 the latest spice simulation and design tools for creating stateoftheart switching power supplies fully updated to incorporate new spice features and capabilities, this practical guide explains, step by step, how to simulate, test, and improve switch mode power supply designs. Free smps books download ebooks online textbooks tutorials. However, in contrast to the old low frequency transformers and. This is done by operating a bipolar transistor or mosfet pass unit. An introduction to switchmode power supplies application. Switchmode power supplies for all your power supply repair. Switched mode power supplies have become ubiquitous in electronics as they provide precise voltages including high power with very high efficiency. A recent innovation is our greenchip family of highly integrated, intelligent, multichip modules mcms that dramatically reduces the standby power consumption of any smps.
It also provides real smps examples, and identifies several application notes and. Once that was complete, we ran the same test on the bad power supply and viewed the results. This manual includes basic information for switching power supply, general. Those experienced electronic repairers know that having the right procedure to troubleshoot and repair power supplies is the key to longterm success look, if you have a wealth of knowledge regarding switch mode power supplies theories, but no practical on repairs, what good is that.
How to repair a switchmodepowersupply smps homemade. Troubleshooting switch mode power supplies giangrandi. This application note provides stepbystep instructions on how to perform a broad range of power analysis measurements on your switch mode power supply smps, as well as detailed. Brought to you by jestine yong slot technical department. Switchmode power supply, reference manual on semiconductor.
Of course we expected the damaged diode cr12 to fail but several other components showed important signature differences. A brief discussion is given to the advantages and disadvantages of a linear regulator versus a switch mode power supply. Switch mode power supplies smpss are used in a range of applications as an efficient and effective source of power. He gives a broad explanation as to how switched mode power supplies work as well as discusses some of the reasons these devices tend to. Based in hornsby, sydney serving all australia and beyond. Mode power supply reference manual should prove useful. The output voltage is controlled by varying the duty cycle, frequency or.
Power supply troubleshooting and repair tips duration. So with no additional wait, listed below are the commonly asked questions which can help you power fix information within your mission to troubleshoot and fix malfunctioning smps units. Of course, like any good troubleshooters and according to the pcb troubleshooting flowchart we gave the power supply a good visual inspection. These power supplies offer a greater power conversion and reduce the.
Newermodel quarterbrick power supplies can supply 250 watts and more of electrical power. This kind of unregulated dc voltage is most often derived from the utility ac source. Embedded switch mode power supplies smps rs components. Traditional power supplies drop the voltage at the mains input using a transformer, rectify and smooth the transformer output, and then use a transistor as a variable resistor to regulate the output voltage. F 12 w low profile modular dc power supplies for electrical cabinets type 78.
The repair of switch mode power supplies smps is economically a good investment for electronics repair shops and for hobbyists. Short for switchedmode power supply, smps is a power supply that uses a switching regulator to control and stabilize the output voltage by switching the load current on and off. Dont waste anymore of your precious time to search from the internet to learn the basic repair. Switchers are often described in terms of bricks, halfbricks, and quarter bricks. An introduction to switch mode power supplies sep 27, 2007 abstract. Really there power supply repair guidebook is an instantly downloadable handbook that is really clear to see, and loaded with phasebyaction image guidelines. Switch mode power supply power supply repair power supply. Also a brief explanation about the difference between linear and switch mode power supplies. Regardless if you are fixing and troubleshooting plasma tv, vcd, lcd tv, monitor, dvd, cctv, printer, satellite receiver, xbox, audio equipment, atx power supplies, power adapter, data projector, you absolutely must have this unique effective book to demonstrate you the way to be an expert on switch mode power supplies repair and smps troubleshooting in just 7 days guaranteed. This reference manual contains useful background information on switching power supplies for those who want to have more meaningful discussions and are not necessarily experts on power supplies. A friend asked me to see if i could repair a couple of iota dls55 series m switchmode power supplies. Above is the output waveform of the switch mode power supply. Notes on the troubleshooting and repair of small switchmode.
Power supply repair switch mode power supplies repair. Go here to learn more about this downloadonly switch mode power supply repair book. The filter circuit is used to regulate the output voltage of the switch mode power supply in order to get the pure constant dc voltage. Troubleshooting a switching power supply part 1 circuit. The efficiency of these power supplies requires low loss power transistors and the design requires measurement of highly dynamic voltages. Topologies of switch mode dcdc converters, dc transfer functions, efficiency, devices, chokes and transformers for switched converters, dynamic response in open and closed loop, resonant converters, design of feedback networks.
He gives a broad explanation as to how switched mode power supplies work as well. This book covers switchedmode power supplies that you may encounter in modern consumer electronic products, and focuses on the most common supplies found throughout the industry. Switch mode power supplies repair guide donwnload pdf. Current limit the power supply to a few amperes and apply power across the shorted terminals. Switchmode power supplies communications manual t2 omron companies shall not be responsible for conformity with any standards, codes or regulations which apply to the combination of the product in the buyers application or use of the product. Switch mode power supply here is a small list of the types of power supples we repair. And a large part of that detail lies in the practical domain, largely because of the typically small number of microseconds of switching periods involved, and the even smaller tens of nanoseconds of switch transition times all these, in effect accentuating various secondorder effects, that eventually end up playing prime havoc with normal. Switch mode power supply high voltage power supply high current power supply linear power supply dc power supply dc battery chargers if you need your power supply tested or. Smps or switch mode power supply repair and troubleshooting is one of the most exciting circuits for a technician or engineer. For details, refer to the s8fsg switch mode power supplies datasheet cat. Switch mode power supply smps applications generally involve power adaptors, desktop power, or server power. Very often when i attempt to repair electronic devices, either mine or from friends, i find out the problem is with the power supply which these days is most often a switched mode power supply smps. Power supply repairtroubleshooting, testing, problems and.
Power supplies of most makes and models from all industries including defence, medical, telecommunications and industrial applications are repaired. A switchedmode power supply is an electronic power supply that incorporates a switching. Then use the thermal camera to observe where the board is heating up. Before you place an order, please read and understand agreement for using the product available on omrons latest best control devices omron, general brochure or omrons website. Switchmode power supply troubleshooting safety the primary danger to you is from the input side of the supply which is directly connected to the ac line and will have large electrolytic capacitors with 320 v or greater dc when powered often, even if the supply does not work correctly and for some time after being unplugged especially if the power.
The main advantages are high efficiency, low cost, low weight and size. This article is for the engineer who has minimal experience with switch mode power supplies. Be careful not to exceed the voltage ratings of any components on this node. Detailed formulas with founding equations are included. However, one drawback is that they require a more complex design. Examples of power supply equipment that we regularly repair includes converters, amplifiers, rectifiers, ups, switched mode power supplies, dc regulated power supplies and ac power supplies from medical lasers and radio broadcasting to ships anchors and radar systems. Once the visual inspection and part replacement is complete, the. Switch mode power supplies are a popular and sometimes necessary choice for dcdc power conversion. It consists of primary and secondary section and has lots of types of components in it to make the power supply work. Switch mode power supplies smps are now standard for the majority of our. Switch mode power supply power supply repair power. Linear regulated power supply and switched mode power supply smps.