A device that is mostly used to change the voltage in an alternating current (AC); however, it can also be used to maintain the same voltage but act as an electrical isolator. The most common type is the laminated core transformer found in power supplies. Made of steel laminations wrapped with two coils of wire, the ratio of windings between the "primary" input coil and the "secondary" output coil determines the voltage change. For example, if the primary has 1,000 windings and the secondary 100, an input of 120 volts is changed to 12v.
Via ElectroMagnetic Induction
There are numerous transformer architectures, and they span the size gamut. Small ones are used in the myriad black boxes that plug into the wall and create low DC voltage for every electronic gadget, while transformers weighing tons are used to transmit 50,000 volts of AC over the nation's power grid. However, they all work via electromagnetic induction. The changing current in the primary coil induces a voltage across the secondary coil.
Switching Power Supplies
The greater the current needed to power the device, the thicker the wire in the coils and the larger the transformer. However, if a high frequency is used, the number of windings can be reduced to make the transformer small. To accomplish this, the incoming voltage is converted to DC (rectified), and a high-frequency oscillator pulses a transistor that passes the rectified voltage as square waves into a "pulse transformer." The on/off DC pulses cause the changing current in the primary coil just the same as AC does. This square wave generation turns a power supply into a "switching power supply." See power adapter, power supply and wall wart.
The Switching Power Supply
In order to reduce the number of windings in transformer coils, a high frequency pulse transformer is used. This is a hypothetical example; voltages and frequencies vary. For example, the oscillator can generate frequencies from 1 kHz to 200 kHz. Following is a simplified circuit diagram of this power supply.
Via ElectroMagnetic Induction
There are numerous transformer architectures, and they span the size gamut. Small ones are used in the myriad black boxes that plug into the wall and create low DC voltage for every electronic gadget, while transformers weighing tons are used to transmit 50,000 volts of AC over the nation's power grid. However, they all work via electromagnetic induction. The changing current in the primary coil induces a voltage across the secondary coil.
Switching Power Supplies
The greater the current needed to power the device, the thicker the wire in the coils and the larger the transformer. However, if a high frequency is used, the number of windings can be reduced to make the transformer small. To accomplish this, the incoming voltage is converted to DC (rectified), and a high-frequency oscillator pulses a transistor that passes the rectified voltage as square waves into a "pulse transformer." The on/off DC pulses cause the changing current in the primary coil just the same as AC does. This square wave generation turns a power supply into a "switching power supply." See power adapter, power supply and wall wart.
The Switching Power Supply
In order to reduce the number of windings in transformer coils, a high frequency pulse transformer is used. This is a hypothetical example; voltages and frequencies vary. For example, the oscillator can generate frequencies from 1 kHz to 200 kHz. Following is a simplified circuit diagram of this power supply.
 | Reproduced with permission from Computer Desktop Encyclopedia. Copyright (c) 1981-2009 The Computer Language Company Inc. All rights reserved. |
Additional Resources
- Bumblebee DIY Edition 2.0 (Mobile)
- A theme dedicated to Transformer. The best Bumblebee theme ever. Nice design in every detail. You won''t miss it as a Transformer fans! The very best theme is now updated according to many users'''' feedback: We made the theme''''s icons position as much as factory default, so you can enjoy...
- Software downloads 2009-11-05
- Bumblebee DIY Edition-COPY (Mobile)
- A theme dedicated to Transformer. The best Bumblebee theme ever. Nice design in every detail. You won''t miss it as a Transformer fans! The very best theme is now updated according to many users'''' feedback: We made the theme''''s icons position as much as factory default, so you can enjoy...
- Software downloads 2009-11-05
- Bumblebee DIY Edition (Mobile)
- A theme dedicated to Transformer. The best Bumblebee theme ever. Nice design in every detail. You won''t miss it as a Transformer fans! The very best theme is now updated according to many users'''' feedback: We made the theme''''s icons position as much as factory default, so you can enjoy...
- Software downloads 2009-11-05
- Lucid Electronics Workbench 1.02.0004 (Windows)
- Calculate the value of a load resistor for a Light Emitting Diode LED based on supply voltage and LED characteristics. This application contains a number of standard LED products to choose from. After the value of the load resistor is calculated, a table of standard resistor values can be displayed...
- Software downloads 2009-10-20
- How the cordless Powermat charging system took my iPod touch hostage [review]
- Unnecessary..... POS if you ask me!Cordless charging will work only whenit will be standardized and built into the various devices.what about solar-charging wireless?i've heard it was on the drawing boards...has anyone refined this 'green tech' to the point where it can be relied on?Oh, well... The transformer is such an...
- Discussion threads 2009-10-16
- 2010 Lexus IS 350 C
- Photo gallery:2010 Lexus IS 350 CWhen Lexus chopped the top off the IS model, it not only added a convertible to its lineup, but made some much-needed updates to the cabin tech. The 2010 Lexus IS 350 C uses a retractable hard top. We like the extra weather protection provided...
- Product reviews 2009-10-13
- (Photos: Lego fans descend on BrickCon 2009)
- That's VoltronThat's not a Transformer, it's Voltron. A very good likeness too. Omg a transformer?Comeon!! Everyone knows of Voltron unless ya lived in a cave somewhere!!! lmaoLOL It is indeed Voltron!I was admiring that until I read the caption, funny how they did not recognize Voltron. 80's FAIL!The reporter...
- Discussion threads 2009-10-07
- Bumblebee Theme(default hierarchy) 2.0 (Mobile)
- A theme dedicated to Transformer. The best Bumblebee theme ever. Nice design in every detail. You won''''t miss it as a Transformer fans! The very best theme is now updated according to many users'' feedback: We made the theme''s icons position as much as factory default, so you can enjoy...
- Software downloads 2009-09-28
- Bumblebee Default Icon (Mobile)
- A theme dedicated to Transformer. The best Bumblebee theme ever. Nice design in every detail. You won''t miss it as a Transformer fans! The default icon version especially for those faithful user of BB. Those familer icons looks like their old friends , even though you cann''t always see them,...
- Software downloads 2009-09-24
- Bumblebee Theme (Mobile)
- A theme dedicated to Transformer. The best Bumblebee theme ever. Nice design in every detail. You won''t miss it as a Transformer fans! A product of MMMOOO Premium Service : 1. Premium class in quality & designing 2. Customized service with product: You can order from us the same product...
- Software downloads 2009-09-16
- Leica announces new M9 and X1 digital cameras
- $8000 USD?!Seriously, $8000 USD. OMG, it better have some cool transformer like tripod, that extends out on it's own as needed, and terminator liquid metal lenses that morph on to it at the switch of a electrostatic based touchscreen.Seriously? Don't they know the economy is in the can?...
- Discussion threads 2009-09-09
- TextWrangler 3.0 (Mac)
- TextWrangler is a powerful and richly-featured tool for composing, modifying, and transforming text stored in plain-text files. TextWrangler is a... General Purpose Text Editor Programmer's Text Editor Unix And Server Administrator's Tool Powerful Text Transformer And Manipulator Product Developed In The Best Traditions Of Bare Bones Software
- Software downloads 2009-08-25
- Netgear unveils 4-port XAVB1004 Home Theater Internet Connection Kit
- still a small portion of TVsthose that do have the built in ethernet are brand new. What most are doing now are hooking up small computers to the TV for weather, movies, games, and anything that they would do at the computer desk. This time they have their...
- Discussion threads 2009-08-12
- Seagate External Desktop Drive - hard drive - 1 TB - Hi-Speed USB
- No wonder WD is kicking thier a**I bought one of these drives from Best Buy. Things seemed OK until it was plug overnight. In the AM I tried to ghost my operating system to it and kept getting errors. Also the drive is clicking which is never a good...
- Discussion threads 2009-08-09
- Layer 7 Technologies Security in the Cloud
- Paul Rochester, CEO, and Scott Morrison, VP Engineering and Chief Architect, of Layer 7 Technologies, dropped by virtually to introduce me to their company's technology and the philosophy behind their products. After a while, I was able to understand the approach they were taking and how extensible and flexible it...
- Blog posts 2009-07-30
- Voice Transformer 1.4 (Mobile)
- Voice Transformer offers you nine unique ways to change your voice, and also to use multiple voice effects at the same time. Try deep bass to sound like Arnold Schwarzenegger, then add echo to channel your inner Darth Vader. Voice Transformer even lets you adjust the amount of the effects...
- Software downloads 2009-07-16
- ABBYY PDF Transformer 3.0 (Windows)
- ABBYY PDF Transformer 3.0 is an easy-to-use PDF utility for quickly converting, creating, editing and saving PDF document. Based on award-winning ABBYY document conversion technology, this sophisticated PDF conversion solution can easily convert PDFs to Microsoft Office formats in 184 languages with only a click of the mouse. With accurate...
- Software downloads 2009-07-15
- Is Twitter the new business card?
- Is Twitter the new business card?Twitter is the Rich Man's business cardHi Jennifer,I think that Twitter has a very high potential of becoming a business card, but a lot of people are web-savvy, but are not rich enough to afford a web-enabled mobile device yet. Connecting asynchronously should also be...
- Discussion threads 2009-05-06
- Get involved: build me your perfect tech-filled house
- Get involved: build me your perfect tech-filled houseBeer taps.http://craziestgadgets.com/2008/11/26/beer-tap-system-with-lcd-tv/RE: Get involved: build me your perfect tech-filled houseEvery day should start with kitty:http://www.amazon.com/Hello-Kitty-Clock-Pink%252f-%2528KT2053%2529/dp/B0015ESWHI/ref=pd_bbs_sr_1?ie=UTF8&s=toys-and-games&qid=1240923927&sr=8-1RE: Get involved: build me your perfect tech-filled houseNeeds:PS3 - $399 plays Blu-rayLogitech Cordless mediaboard pro (for both PS3 and TV-connected PC) - $7032" Samsung LCD TV - $549Belkin...
- Discussion threads 2009-04-28
- D-Link turns every power outlet into wall-to-wall network
- D-Link turns every power outlet into wall-to-wall network...nothing newI've had this running in my home for about a year now...I mean, I get that this may be a new product for D-Link, but don't go making it sound like they've invented something new here. They're just catching on, there are...
- Discussion threads 2009-04-15
Neighboring Terms
Premier Vendor Content Whitepapers, webcasts & resources from our Power Center Sponsors
- Microsoft Dynamics CRM Online - Free Six-Month Trial for Eligible Organizations
-
Microsoft Dynamics CRM Online provides fast online access, simple contact management and better sales performance for a low monthly cost - the best value on the market today.
- Learn more about the free, six-month trial offer>>
- New Online Dashboard for IT Leaders
-
Read about top issues IT decision-makers face every day, plus get cost-effective solutions to real-life IT problems.
- Learn more >>
- Keep Up With The Latest In Document Management with The DocuMentor.
-
Doc delivers the scoop on today's enterprise content management, printer maintenance, and all other issues related to document management. It's the DocuMentor Blog.
- Learn more >>
SmartPlanet
- Thought-provoking progressive ideas on diverse topics that intersect with technology, business, and life, and matter to the world at large. Visit SmartPlanet
- More from IBM
-
- Innovate your business' process model, play against the market, compete against others on our scoreboards and WIN! Try INNOV8 2.0: A BPM Simulator
- Enabling Real-World Business Transformation through IBM Service Management Read the EMA Analyst Report
