TM

October 2006

Power-One (PWER) Acquisition Presentation

2

Disclaimer

This presentation contains forward-looking statements, which are made pursuant to the Safe-Harbor provisions of the Private Securities Litigation Reform Act of 1995. Words such as “forecast,” “expect,” “anticipate,” “will,” “looking,” “believe” and similar expressions reflecting something other than historical fact are intended to identify forward-looking statements, but are not the exclusive means of identifying such statements. Forward-looking statements are not guarantees, but rather are predictions of and make certain assumptions regarding anticipated future results. Please refer to the end of this presentation for complete disclaimer.

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Power-One Mission Statement

To be recognized as the leader in system-level

power and power management solutions from

AC to the IC in the communications and high-

technology markets, utilizing our technical

leadership to deliver comprehensive low-cost

solutions; providing increasing value to

customers, employees, and investors

4

Power-One Power Supplies Are Everywhere

Over 30 million power supplies shipped & Silicon…

Our products convert, process & purify electricity to the high levels of quality, reliability, & precise direct current

required by the digital economy

Soon: Custom, Alternative Energy, digital motor controls, specialty transportation & systems

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Power Conversion Products for Communications & High-technology Infrastructure Markets

DC/DC Power Plus Digital Power

ManagementControls Power on thePrinted Circuit Board

AC/DC Power Powers Telecom, Networking

& Industrial EquipmentControls Power at the

System Cabinet

6

Power-One Today

• 30+ years of success• One of the world’s top power supply companies

–Broad-line power conversion supplier – 100’s of standard product families

–Over 2,500 employees –Top brand name & quality reputation–Industry leading Gross Margins

• Five acquisitions since 1999 • Highly-automated worldwide manufacturing• Strong balance sheet (~$72M in cash- no debt)• Revenues est. at $300M in 2006 • Investing ~$7M/yr in R&D for silicon design

Today, Power-One is the technology leader in power; a consolidator; and a developer of silicon products

(Soon 4000!)

(Soon six!)

(Soon $530-550M)

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Where Power-One Excels

• Worldwide Mfg. and R&D (Asia, Americas & Europe)

• Worldwide Customer Service and Support Including Field Applications, Sales & Sophisticated IT Infrastructure (EDI)

• Technology:– In-house silicon development and packaging capabilities

– Digital Power Management, Z-OneTM Digital IBA, the first complete power conversion AND power management solution

– Density leadership in DC-DC bricks and POLs

– Leadership in AC Front Ends and Telecom Power Systems

– Industry’s highest efficiency and power density

• Competitive on a world class level

• We are a complete supplier from AC to the IC

TMA Digital Power Revolution

Conversion … Communications… Control

Digital Power Revolution--- ZZZZ

9

Power Management and Power Conversion Becomes One … with Digital Technology

Conversion

Control (Pwr. Mgt.)

Communication

Goal: 20% Market Share in 5 Years

10

“BRICK” DC/DC

Converter

Analog Controller

V5V5

48 V “BRICK” DC/DC

Converter

POL3.3V

V1V1

POL3.0V

V2V2

POL2.5V

V3V3

POL1.8V

V4V4

POL POL POL

V6V6 V7V7

The “Before” – Unmanageable with Analog

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DPM

“BRICK” DC/DC

Converter

48 V

The “After”: Z-One DIGITAL IBA™The “After”: Z-One DIGITAL IBA™

V1V1 V2V2 V3V3 V4V4

V5V5 V6V6 V7V7

Z-POL

Z-POL

Z-POL

Z-POL

Z-POL

Z-POL

Z-POL

I2C fromHost

System

I2C fromHost

System

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8-output Power System Comparison

Z-OneDigital IBA

IBA with Analog Power Mgmt

200+

600+

~10 in2

8 Weeks

Limited

~$100+

99

<100

<100

3.8 in23.8 in2

3 Days3 Days

Virtually UnlimitedVirtually Unlimited

~$90~$90

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Results for Z-One Digital Power• We have a significant head-start on the competition

• The Z-series disruptive architecture is a true revolution in power

• Licensed technology (second sourcing)– Benefits in broader/larger market, licensing fees & technology sharing– Module 2nd source in Dec. ’04 with C&D Technologies (top 5 supplier)– Semiconductor Z-affiliate announced with Atmel in July’05; and with Micrel LDO

(Low Drop-Out) regulator IC in Sept ‘06– Recent announcement – Silicon Labs is joining the Z-Alliance– Meeting with other potential partners

• Customers who implement the “Z” can offer products with additional system features and benefits; and with faster TTM (time to market)

• New markets opened, e.g., Storage & Server, Military, Aerospace & Security (total POL market exceeds $1.0 billion)

• Core business is growing as a result of the “Z”

• ~70 Z-One board-level design wins & growing (now with top 10 cust.)

• Significantly more embedded in the customers’ systems architecture

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Transaction for Power Electronics Group of Magnetek, Inc.

• Power-One, Inc. has signed a Definitive Agreement to acquire the Power Electronics Group (P.E.G.) of Magnetek, Inc.

• P.E.G. has been operating essentially as an autonomous business unit for many years

• Transaction Closing is expected to be in October

• Power-One has secured $50M of acquisition financing via an 18 month loan. We will be investigating a variety of options for longer-term financing that is more accretive

• The company will use a portion of its cash and investments, but will keep ~$40M on our balance sheet. Total post-closing debt, with financing will be 65-70M

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Overall Transaction Assets

• Three main factories

– 230K sq. ft. in Shenzen (Baoan) China

– 180K sq. ft. in Valdarno, Italy (Includes R&D and Admin, with low-cost “feeder plant” in Hungary)

– 50K sq. ft. in Chatsworth, CA

• Best-in-class R&D Center (80+ experienced engineers)

• Custom product capability

• New applications, like Alternative Energy (AE) & digital control for motors

• High-volume purchasing leverage

Chatsworth, California

Valdarno, Italy

Shenzhen, China

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Liabilities – What Power-One Will Not Get

• Only taking the liabilities of the parent company (Magnetek, Inc.) that are for the Power Electronics Group

• The transaction does not include the liabilities of the parent company:

– Fluorescent lighting lawsuit and liabilities will remain with Magnetek

– Employee benefits and pension liability of Magnetek, Inc. is retained by them

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Excellent Strategic Value

• Purchase price of ~$72M in cash, plus $17M debt

• Grows Power-One’s revenue by over 50% with overall purchase price of approximately 0.5x forecasted sales for 2007

• Power-One will become a ½ billion dollar company in 2007; forecast sales range from $530M to $550M

• Power-One continues to be a consolidator with this 6th acquisition in 8 years

• Lowers Overheads & Operating Expenses

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Strategic Synergies & Importance

1. Accretive in Early 2007

2. R&D resources and technologies

3. Size and purchasing power of larger company

4. High-volume, low-cost China operation

5. Alternative Energy initiative

6. European operations expanded

7. Augments top customer base

8. Customs and new applications widen market

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Strategic Synergies & Importance #1 – Accretive in Early 2007

• The acquisition is strategic and accretive– Will be accretive in Q1 of 2007

• Synergies will be additive to earnings per share

~$9M ($0.10 per share) in 2007

~$20M ($0.22 per share) in 2008

• Although acquisition has lower gross margins than Power-One, it also has lower operating costs. Post merger will see margins in the high 20’s%, but should gradually increase throughout 2007 to above 30%, with further improvements into the low 30’s% in 2008

• Primary drivers for margin improvement are synergies in purchasing and manufacturing

• Operating expenses of ~30% of sales will immediately decrease into the mid to high 20’s% range; gradually decrease throughout 2007 with a target goal in the low 20’s%

• Cash generation expected to begin in 2007

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Strategic Synergies & Importance #2 – R&D Resources And Technologies

• Experience (breadth and depth) in Italy with 80+ Engineers

• Augments other European Design Centers in Switzerland and Slovakia

• Increased IP portfolio • Low cost for experienced R&D

personnel • Products range from smart motor driver

and control circuits to large 50KW power modules

Custom Power Supplies

Inverters

High Density Data Storage

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Strategic Synergies & Importance #2 (Cont) – R&D Resources And Technologies

• 90% of products are digital implementations with micro/DSP and software– Fewer competitors - less commoditization

– Higher margins over time

– Greater functionality - market diversity

– Higher performance

– Software-driven with reduced parts count, higher reliability

• Augments Power-One’s board-level Z-One® digital power management capabilities

DigitalSmart Appliance

Control & Management

DSP-based Motor Controls

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Strategic Synergies & Importance #3 – Size & Purchasing Power Of Larger Company

• Catapults Power-One into becoming the 6th largest power supply company in the world – from 16th position

• Combined sales in 2007 is forecast to be in the range of $530M to $550M

• Economy-of-scale facilitates ability to compete with the largest competitors in purchasing components

• Size and breadth of products are important in servicing the Server/Storage markets

• Material purchases is largest part of COGS; this is the most significant and fastest way to achieve synergy

23

Strategic Synergies & Importance #4 – High-volume, Low-cost China Operation

• China manufacturing expertise– 500+ manufacturing people; local

management for 5+ years

– 230,000 sq. ft. of operations - with capacity & scaling capability

• Factory is close to current Power-One factory that builds the Power Systems product line

• Added manufacturing in China addresses high-volume need for future growth

• Critical mass in Asia has been reached with Power-One factories handling high-volume demand; Contract Manufacturers (CM) will continue to support mid-volume

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Strategic Synergies & Importance #4 (Cont.) – High-volume, Low-cost China Operation

• New China operation reduces cost and increases control. Reduces issues with current CM arrangement

• Acquisition will increase profitability with higher-volume jobs. No “dual” profits required

• Customers are driving for more control over the mfg. process. Main Competitors do not use CM’s

• Allows better service and support of local customers

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Strategic Synergies & Importance #5 – Alternative Energy Initiative In Power Inverters

Solar – Wind – Fuel Cells• High reliability and efficiency

power converters

• High power-density & compact size

• Primary energy source control

• Grid interactive control

• System level control

Wind PowerConverters

Photovoltaic Inverters

Compact Fuel Cell Power

Conditioners

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Strategic Synergies & Importance #5 (Cont) – Alternative Energy Systems

Aurora PrePack Panels (Integrated Solar PV power

inversion system)

Aurora® PVI-Wind Interface adapts solar PV power inverter for use with wind turbines

MultiMode World Inverter (MWI) Tailors power input from any Alternative Energy Source to any AC or DC power application (grid interface and/or local load)

Power conditioners and interfaces for Compact Fuel

Cells

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Strategic Synergies & Importance #6 – European Operations Expanded

• Italy – 180,000 sq. ft. of R&D, Admin, & Operations – Impressive R&D center– Specialized products and manufacturing

• Alternative Energy Systems• Intelligent digital Motor Driver and Controls • Specialty transportation

– Excellent mid-volume/complex product capability

• Low-cost “feeder plant” in Hungary (30K sq. ft.)• Local support for European regional customers

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Strategic Synergies & Importance #7 – Acquisition Augments Premier Customer Base

Bottom Row Shows Significant Additions to PWER Base

29

Strategic Synergies & Importance #8 – Customs & New Applications Widen Market

• Adds “custom” capability to Power-One’s standard product offerings

• Large Custom market

– AC/DC Custom market in 2007 is ~$7B, which is more than twice as large as Standard + Modified AC/DC market. Additionally, the Custom market is growing ~7-9%... more than twice as fast as the Standard market.

– Customers have been asking Power-One to do more Customs; the issue has been R&D resources. The acquisition will greatly expand the resources.

Segway “HT”

Digital Business Machines

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Strategic Synergies & Importance #8 (Cont) -- Customs & New Applications Widen Market

Other New Applications• Intelligent motor drive and controls

– Embedded, Variable-Speed Motor Drives

– Temperature Control Boards

– User Interfaces

• Specialty transportation products– 55kW multi-voltage APSS for European

Intercity Trains

ASSIEME MODULI IGBT

3E864100000

SCHEDA CONTROLLO

9153E860203

ASSIEME SENSORI 1 C.B

3E864600000

ASSIEME SENSORI 2

3E864700000

INDUTTANZA FILTRO LINEA

82100020ATM

INDUTTANZE DI USCITA 82100021ATM

INDUTTANZE CARICABATTERIE

82100017ATM

DISSIPAT. PICCOLO

3E864500000

TRASF. CARICABATTERIE 82100016ATM

COND.1 E COND.2

80102358ATM

CAMBIOTENSIONE

3E864800000 ALIMENTATORE 3E864300000 TRASFORMATORE

TRIFASE 82100019ATM

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Synergistic with Other Products• Purchasing power of high-volume components will carry-

over to lower-volume components• Engineering collaboration between AC/DC R&D• Digital techniques in AC/DC• Standardization of Custom products• Capitalize on Power-One distributors and channels

• Cross-selling opportunities, e.g., Telecom products

Control Unit

Electronic Power

Distribution Unit

‘Smart’ Solid-State Circuit Breakers

DC Power SystemsRectifie

rs

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Integration Plan

• Objective is to combine both into a stronger company

• Will be integrated into Power-One’s functional structure

• Allows quick actions and savings – functional orientation will facilitate integration

• Materials & purchasing cost reductions will be 1st priority

• Move high-volume products from CM to new China factory. Note: new China factory in Baoan is very close to our current factory in Shekou. Both are in Shenzhen.

• Shift Italy’s R&D team to focus on much larger business deals; from smaller to larger ($5M - $10M) projects.  Power One has several large deals pending.

• Globally – Operations, Engineering, and Marketing & Sales forces will be combined “Day 1”

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Integration Status

Synergy leadership teams have been identified and planning is in place to timely capture savings

In-depth discussions, meetings, and site visits were used both for Due Diligence and “Fast-track” integration

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Acquisition Supports PWER’s 2006 Goals (In Prior IR Presentations – and Acquisition Impact)

Pre-acquisition Goals Acquisition Impact

$160M+ added

$530-550M in 2007

Increase engineering capabilities

Introduce new products/applications

Increase AC/DC presence both in channel & products

Adding resources in Europe (Slovakia & Switzerland)

Execution of higher-volume projects with Server & Storage customers

Decrease material costs

10-15% growth forecast in 2006

Combination will benefit

China factory will be used for high-volume manufacturing

Italy & Hungary

Custom AC/DC products

Alternative Energy, Transportation, Smart Motor Drive & Control Systems

Superb R&D Center with 80+ experienced engineers

35

Power-One’s History & Strategic Direction

1997 1998 2001

A technology leader in powering communications. Integrated five acquisitions, developed silicon & digital

power mgt.

20001999

Founded as AC/DC power conversion company

1973

Strategic shift to communications

infrastructure markets &

acquisitions

Acquired Melcher

Acquired IPD

AcquiredHC

AcquiredPowec

Power Systems (North America)

DC/DC Bricks (North America)

DC/DC Conversion (Europe)

Power Systems (Europe/Asia)

AC/DC – North America

Initial Public Offering

(IPO)

2002 2003

Silicon Initiative

Acquired di/dt

High-density Bricks & POL’s

Silicon R&D Center Startup

Silicon Division

2004

Silicon POL’s + 1st Power Mgt.

2005

Strategic DirectionStrategic Direction2006

AcquiringPEG of MAGCustom Products & China Mfg.

Entered Server/Storage

markets & acquiring Custom

capability

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Power-One’s New Global Footprint

Dominican Rep.Carlsbad, CA

Switzerland

Australia

SingaporePenang, Malaysia

Shekou, Shenzhen, China

Manufacturing Centers

R&D Centers

Camarillo, CA

SlovakiaAndover, MA

Ireland

San Jose, CA

Baoan, Shenzhen, China

NEW Mfg Centers

NEW R&D Centers

ItalyHungary

Chatsworth, CADallas, TX

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Summary of Potential SynergiesP.E.G. Power-One Combined Synergy

Product Orientation

• Customs • Standards • Full Product Portfolio – the best in power

Operations • Strong AC in China (China);• Excellent Italy mid-volume/complex product capability

•Strong DC/DC in Asia & Dom. Rep.• Strong AC in mid-volume in D.R.

• Can compete with the largest competitors• Combined purchasing power

Increased Sales

• Strong Customer Relationships• Diverse Customer Base• $160M

• Largest datacom customers• ATE & Transportation Customers • Server/Storage ramping• Global Sales Presence• $300M+ in 2006• Largest Distribution Base

• Increased market share• Cross-selling opportunities• Customers are different; increased penetration• ½ Billion!

Financials * Sound Balance Sheet • $75M in Cash• Zero debt

• Very secure financially• Ability to fund future growth & opportunities

Orientation • Power Only • Power Only • The ONLY top-10 power company that is exclusively power• Top Brand-name recognition

Technology/

R&D

• Innovation AC/DC • Very High Power• Digital Implementations (DSP & uControllers)• Software/Firmware• Very Diverse Applications

• DC/DC Bricks• Digital Power Mgt (Board Level)• High efficiency

• The best in the industry• IC’s to AC • New Applications (Solar/Wind/Utility)• Engineering collaboration• Increased IP portfolio

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Growth Opportunities

Communications & Industrial Markets

Standard Products

Power Systems(Indoor)

AC/DC Power Supplies

DC/DC Bricks

Server & StorageMarkets

Custom Products

Power Systems(Outdoor & Access)

AC/DC Front-ends

Analog POLs

Z-One™ Digital Power-Digital POLs-Digital Power Mgt.

NEW OPPORTUNITIES1. New Markets2. New Products3. Digital Power

CORE GROWTH1. Technology Leadership2. High Density/Efficiency3. Broad Product Portfolio

Acquisitions

39

Significance of Acquisition for Investors• Power-One is a consolidator and can compete with

biggest competitors

• More opportunities with large, global, well-funded company in fast-growing markets

• Acquisition is very accretive, very quickly

• Power-One is the only significant “Pure Power” play

• High synergistic and strategic value in the acquisition

• Augments and helps fund continuing digital power developments

• Power-One forecasts 4th quarter range to be between $120-130M with acquisition, depending upon closing date; $530-550M in 2007.

40

Other Power-One “Take-a-ways”

• 2005 was a return to profitability year (Q3 & Q4)• 2006 is a return to growth; Bookings & Backlog are at the highest

levels since 2000. Q3 Guidance: $74-78M• Telecom Power Systems should be high-growth business• Server & Storage design wins will turn into revenue (‘06 forward) • AC/DC Front-End business is strong, especially with new products• DC/DC products continued strength in market with bricks & POLs• Z-One™ digital power management gaining momentum

– Z-Alliance includes C&D Technology, Atmel, and now Silicon Laboratories!– Design-wins growing, multiple platforms, top 10 customers– “No-bus” Z-1000 addresses lower end systems – power mgt. for free!– 2nd generation Digital Power Manager now controls non-Z-One devices

• Continuing to forecast 10-15% organic growth for 2006

TM

Thank You!

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Disclaimer & Forward Looking Statements

This presentation contains forward-looking statements, which are made pursuant to the Safe-Harbor provisions of the Private Securities Litigation Reform Act of 1995. Words such as “forecast,” “expect,” “anticipate,” “will,” “looking,” “believe” and similar expressions reflecting something other than historical fact are intended to identify forward-looking statements, but are not the exclusive means of identifying such statements. Forward-looking statements are not guarantees, but rather are predictions of and make certain assumptions regarding anticipated future results. Achievement of actual results are dependent upon and will involve a variety of risks and uncertainties that could cause actual results to differ materially from assumptions and predictions. Such risks and uncertainties include, but are not limited to, the risk that Power-One’s and Magnetek’ businesses will not be integrated successfully; distraction of management as a result of, and the challenges of integration and restructuring associated with the transaction or other acquisitions, and the challenges of achieving anticipated synergies in whole or in part; costs related to the transaction; the possibility that the market for the sale of certain products and services may not develop as expected; Power-One’s ability to manage its international operations; the risk that the process of reconciling certain Magnetek, Inc. financial information to U.S. GAAP could result in changes to Magnetek’ financial statements that adversely impact the Power-One’s pro forma estimates regarding the transaction; the existence or enactment of adverse U.S. and foreign government regulation; the risk that the development of products and services may not proceed as planned; adverse general domestic and international economic conditions including interest rate and currency exchange rate fluctuations; the difficulty of efficiently managing the company’s cost structure for capital expenditures, materials and overhead, as well as operating expenses such as wages and benefits due to the vertical integration of the company’s manufacturing processes; the possibility that the transaction or other contemplated acquisitions may not close; the impact of competitive products or technologies and competitive pricing pressures; potential business disruptions, including labor unrest, work stoppages, or other short or longer term labor disruptions; and other risks that are described from time to time in Power-One's Securities and Exchange Commission reports. See “Risk Factors” in the Company’s 2005 Form 10-K on file with the Securities and Exchange Commission for greater detail regarding factors that constitute cautionary statements with respect to such forward-looking statements, including certain risks and uncertainties that could cause actual results to differ materially from those in such forward-looking statements. Readers of this information are cautioned not to place undue reliance on these forward-looking statements, since, while we believe the assumptions on which the forward-looking statements are based are reasonable, there can be no assurance that these forward-looking statements will prove to be accurate. This cautionary statement is applicable to all forward-looking statements contained in these materials. We undertake no obligation to update, amend or clarify forward-looking statements, whether as a result of new information, future events or otherwise.