Form 425

Filed by ON Semiconductor Corporation

Pursuant to Rule 425 under the Securities Act of 1933

and deemed filed pursuant to Rule 14a-12

of the Securities Exchange Act of 1934

Subject Company: Catalyst Semiconductor, Inc.

This document contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These forward-looking statements include, but are not limited to, statements related to the benefits of the proposed transaction between ON Semiconductor Corporation (“ON”) and Catalyst Semiconductor (“Catalyst Semiconductor”) and the future financial performance of ON. These forward-looking statements are based on information available to ON and Catalyst Semiconductor as of the date of this release and current expectations, forecasts and assumptions and involve a number of risks and uncertainties that could cause actual results to differ materially from those anticipated by these forward-looking statements. Such risks and uncertainties include a variety of factors, some of which are beyond ON’s or Catalyst Semiconductor’s control. In particular, such risks and uncertainties include difficulties encountered in integrating merged businesses; the risk that the transaction does not close, including the risk that the requisite stockholder and regulatory approvals may not be obtained; the variable demand and the aggressive pricing environment for semiconductor products; dependence on each company’s ability to successfully manufacture in increasing volumes on a cost-effective basis and with acceptable quality its current products; the adverse impact of competitive product announcements; revenues and operating performance, changes in overall economic conditions, the cyclical nature of the semiconductor industry, changes in demand for our products, changes in inventories at customers and distributors, technological and product development risks, availability of raw materials, competitors’ actions, pricing and gross margin pressures, loss of key customers, order cancellations or reduced bookings, changes in manufacturing yields, control of costs and expenses, significant litigation, risks associated with acquisitions and dispositions, risks associated with leverage and restrictive covenants in debt agreements, risks associated with international operations, the threat or occurrence of international armed conflict and terrorist activities both in the United States and internationally, risks and costs associated with increased and new regulation of corporate governance and disclosure standards (including pursuant to Section 404 of the Sarbanes-Oxley Act of 2002), and risks involving environmental or other governmental regulation. Information concerning additional factors that could cause results to differ materially from those projected in the forward-looking statements is contained in ON’s Annual Report on Form 10-K as filed with the Securities and Exchange Commission (the “SEC”) on February 12, 2008, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and other of ON’s SEC filings, and Catalyst Semiconductor’s Annual Report on Form 10-K as filed with the SEC on July 3, 2008, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and other of Catalyst Semiconductor SEC filings. These forward-looking statements should not be relied upon as representing ON’s or Catalyst Semiconductor’s views as of any subsequent date and neither undertake any obligation to update forward-looking statements to reflect events or circumstances after the date they were made.

This communication is being made in respect of the proposed transaction involving ON and Catalyst Semiconductor. In connection with the proposed transaction, ON plans to file with the SEC a Registration Statement on Form S-4 containing a Proxy Statement of Catalyst Semiconductor and a Prospectus of ON, and each of ON and Catalyst Semiconductor plan to file with the SEC other documents regarding the proposed transaction. The definitive Proxy Statement/Prospectus will be mailed to stockholders of Catalyst Semiconductor. INVESTORS AND SECURITY HOLDERS ARE URGED TO READ THE PROXY STATEMENT/PROSPECTUS AND OTHER DOCUMENTS FILED WITH THE SEC CAREFULLY IN THEIR ENTIRETY WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED TRANSACTION.


Investors and security holders will be able to obtain free copies of the Registration Statement and the Proxy Statement/Prospectus (when available) and other documents filed with the SEC by ON and Catalyst Semiconductor through the web site maintained by the SEC at www.sec.gov. In addition, investors and security holders will be able to obtain free copies of the Registration Statement and the Proxy Statement/Prospectus (when available) and other documents filed with the SEC from ON by directing a request to ON Semiconductor Corporation, 5005 East McDowell Road, Phoenix, AZ, 85008, Attention: Investor Relations (telephone: (602) 244-3437) or going to ON’s corporate website at www.onsemi.com, or from Catalyst Semiconductor by directing a request to Catalyst Semiconductor, Inc., 2975 Stender Way, Santa Clara, CA 95054, Attention: Investor Relations (telephone: (408) 542-1200) or going to Catalyst Semiconductor’s corporate website at www.catsemi.com.

ON and Catalyst Semiconductor and their respective directors and executive officers may be deemed to be participants in the solicitation of proxies in respect of the proposed transaction. Information regarding ON’s directors and executive officers is contained in ON’s annual proxy statement filed with the SEC on April 4, 2008, as supplemented a Current Report on Form 8-K filed with the SEC on March 17, 2008. Information regarding Catalyst Semiconductor’s directors and executive officers is contained in Catalyst Semiconductor’s annual proxy statement filed with the SEC on August 24, 2007. Additional information regarding the interests of such potential participants will be included in the Proxy Statement/Prospectus and the other relevant documents filed with the SEC (when available).

Filed below is a presentation to ON employees on July 17, 2008 regarding ON’s proposed acquisition of Catalyst.


Employee
Presentation
July
2008


Employee
Presentation
July
2008
Safe Harbor Statement and Non-GAAP Financial
Measure Information
During the course of this presentation, ON Semiconductor may make projections or
other forward-looking statements regarding future events or its future financial
performance.  The words “estimate,”
“intend,”
“expect,”
“plan,”
“should”
or similar
expressions
are
intended
to
identify
forward-looking
statements.
ON
Semiconductor
wishes to caution that such statements are subject to risks and uncertainties that could
cause actual events or results to differ materially.  Important factors relating to our
business, including factors that could cause actual results to differ from our forward-
looking
statements,
are
described
in
our
Form
10-K
and
other
filings
with
the
SEC.
ON
Semiconductor assumes no obligation to update forward-looking statements to reflect
actual results or changed assumptions or other factors.
Some
data
in
this
presentation
may
include
non-GAAP
financial
measures.
You
can
find reconciliations of these non-GAAP financial measures to the most directly
comparable measures under generally accepted accounting principles within the
following
presentation
at
our
website
(http://www.onsemi.com)
at
the
“Investors”
section
under the category “Annual Reports/Financial Releases.”


Employee
Presentation
July
2008
This document contains forward-looking statements within the meaning of the Private Securities Litigation Reform
Act of 1995. These forward-looking statements include, but are not limited to, statements related to the benefits of the
proposed transaction between ON Semiconductor Corporation (“ON”) and Catalyst Semiconductor, Inc. (“Catalyst
Semiconductor”) and the future financial performance of ON. These forward-looking statements are based on
information available to ON and Catalyst Semiconductor as of the
date of this release and current expectations,
forecasts and assumptions and involve a number of risks and uncertainties that could cause actual results to differ
materially from those anticipated by these forward-looking statements. Such risks and uncertainties include a variety of
factors, some of which are beyond ON’s or Catalyst Semiconductor’s control. In particular, such risks and uncertainties
include difficulties encountered in integrating merged businesses; the risk that the transaction does not close, including
the risk that the requisite stockholder and regulatory approvals
may not be obtained; the variable demand and the
aggressive pricing environment for semiconductor products; dependence on each company’s ability to successfully
manufacture in increasing volumes on a cost-effective basis and with acceptable quality for its current products; the
adverse impact of competitive product announcements; revenues and operating performance; changes in overall
economic conditions; the cyclical nature of the semiconductor industry; changes in demand for our products; changes in
inventories at customers and distributors; technological and product development risks; availability of raw materials;
competitors' actions; pricing and gross margin pressures; loss of key customers; order cancellations or reduced
bookings; changes in manufacturing yields; control of costs and expenses; significant litigation; risks associated with
acquisitions and dispositions; risks associated with leverage and restrictive covenants in debt agreements; risks
associated with international operations; the threat or occurrence of international armed conflict and terrorist activities
both in the United States and internationally; risks and costs associated with increased and new regulation of corporate
governance and disclosure standards (including pursuant to Section 404 of the Sarbanes-Oxley Act of 2002); and risks
involving
environmental
or
other
governmental
regulation. Information
concerning
additional
factors
that
could
cause
results to differ materially from those projected in the forward-looking statements is contained in ON’s Annual Report on
Form 10-K as filed with the Securities and Exchange Commission (the “SEC”) on February 12, 2008, Quarterly Reports
on Form 10-Q, Current Reports on Form 8-K and other of ON’s SEC filings, and Catalyst Semiconductor’s Annual
Report on Form 10-K as filed with the SEC on July 3, 2008, Quarterly Reports on Form 10-Q, Current Reports on Form
8-K and other of Catalyst Semiconductor SEC filings. These forward-looking statements should not be relied upon as
representing ON’s or Catalyst Semiconductor’s views as of any subsequent date and neither undertake any obligation
to update forward-looking statements to reflect events or circumstances after the date they were made.


Employee
Presentation
July
2008
This communication is being made in respect of the proposed transaction involving ON and Catalyst
Semiconductor. In connection with the proposed transaction, ON plans to file with the SEC a Registration Statement on
Form S-4 containing a Proxy Statement of Catalyst Semiconductor and a Prospectus of ON and each of ON and
Catalyst Semiconductor plan to file with the SEC other documents
regarding the proposed transaction. The definitive
Proxy Statement/ Prospectus will be mailed to stockholders of Catalyst Semiconductor. INVESTORS AND SECURITY
HOLDERS ARE URGED TO READ THE PROXY STATEMENT/PROSPECTUS AND OTHER DOCUMENTS FILED
WITH THE SEC CAREFULLY IN THEIR ENTIRETY WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL
CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED TRANSACTION.
Investors and security holders will be able to obtain free copies of the Registration Statement and the
Proxy Statement/Prospectus (when available) and other documents filed with the SEC by ON and Catalyst
Semiconductor through the web site maintained by the SEC at www.sec.gov. In addition, investors and security holders
will be able to obtain free copies of the Registration Statement
and the Proxy Statement/Prospectus (when available)
and other documents filed with the SEC from ON by directing a request to ON Semiconductor Corporation, 5005 East
McDowell Road, Phoenix, AZ, 85008, Attention: Investor Relations
(telephone: (602)
244-3437) or going to ON’s
corporate website at www.onsemi.com, or from Catalyst Semiconductor by directing a request to Catalyst
Semiconductor, Inc., 2975 Stender
Way, Santa Clara, CA 94054, Attention: Investor Relations (telephone:408-542-
1200) or going to Catalyst Semiconductor’s corporate website at www.catsemi.com.
ON and Catalyst Semiconductor, and their respective directors and executive officers, may be deemed to
be participants in the solicitation of proxies in respect of the
proposed transaction. Information regarding ON’s directors
and executive officers is contained in its annual proxy statement filed with the SEC on April 4, 2008. Information
regarding Catalyst Semiconductor’s directors and executive officers is contained in Catalyst Semiconductor’s annual
proxy statement filed with the SEC on August 24, 2007. Additional information regarding the interests of such potential
participants will be included in the Proxy Statement/Prospectus and the other relevant documents filed with the SEC
(when available).


Employee
Presentation
July
2008
Why is ON Semiconductor Acquiring
Catalyst Semiconductor
About ON Semiconductor
Organization Overview and
Common Questions
Expectations and FAQs
Employee Resources
Agenda


Employee
Presentation
July
2008
-
The
acquisition
of
Catalyst
Semiconductor
will
add
to
ON
Semiconductor’s
high
gross
margin
analog
and
mixed
signal
products
offerings
-
Catalyst
Semiconductor’s
EEPROM
technology
will
strengthen
our
ASIC
and
power
product
capabilities
expanding
our
ability
to
more
comprehensively
address
our
customers’
needs
-
Catalyst
Semiconductor’s
proprietary
intellectual
property
and
proven
design
capabilities
Size
and
scale
are
important.
ON
Semiconductor
can
provide
Catalyst
with:
Deeper
customer
relationships
and
sales
channels
Integrated
manufacturing
capabilities
An
expanded
addressable
market
Why is ON Semiconductor
Acquiring Catalyst Semiconductor


Employee
Presentation
July
2008
World class, high
volume, cost
effective products
Leading standard
products in
Automotive,
Computing,
Consumer and
Communications
end markets
Industry leader in
power management
Leader in analog,
mixed signal and
EEPROM
technologies
Top 4 player in
EEPROM sector
Proprietary
technology and
proven design
capabilities
Leading standard and custom
products increase customer
value proposition
Expanded analog and mixed
signal design and strong
EEPROM capabilities
Expanded presence in
automotive, consumer and
industrial end markets
Integrated manufacturing
capabilities including advanced
sub-micron Gresham fabrication
facility which can extend the
product roadmap and increase
the total addressable market
A Winning Combination


Employee
Presentation
July
2008
Why is ON Semiconductor Acquiring Catalyst
Semiconductor
About ON Semiconductor
Organization Overview and Common Questions
Expectations and FAQs
Employee Resources
Agenda


Employee
Presentation
July
2008
Vision and Mission of ON Semiconductor
Our Vision
Our Mission
Dedicated to becoming the premier supplier of
Dedicated to becoming the premier supplier of
high performance energy efficient silicon
high performance energy efficient silicon
solutions worldwide
solutions worldwide
To provide our customers with high quality,
To provide our customers with high quality,
cost efficient solutions to solve the demanding
cost efficient solutions to solve the demanding
power and signal management design
power and signal management design
challenges
challenges


Employee
Presentation
July
2008
Industry Dynamics Continue to Favor
ON Semiconductor
Rationalization of the Supplier Base
ON Semiconductor is the one-stop shop for the semiconductor requirements of
our customers
From
custom
ASICs
to
standard
components,
we
are
an
expert
in
power
efficiency with the broadest selection of semiconductor products
We shipped more than 32 billion units in 2007, more than five products for
every person in the world with 95 percent on-time delivery to our key
customer requested dates
Customers and Consumers are focused on Energy Efficiency
Government agencies such as EnergyStar™, California CEC, European Code of
Conduct and the China CSC as well as consumers are focused on the power
consumption of electronic devices
ON
is
a
leader
in
the
Green
wave
with
its
GreenPoint™
power
solutions
and
Greenline™
products that meet these emerging standards at a lower total design
cost
Consumer Driven Semiconductor Growth
High Volume, Competitive Costs, High Quality Levels, Flexible Capacity, Quick
Design Turns


Employee
Presentation
July
2008
Focus on the Right Applications
Factory Automation
Security Systems
Sensor Interfaces
Wireless or Wired Networking
Communications Interface
Industrial
Medical
Implantable Devices
Remote Patient Monitoring
Medical Imaging
Blood Glucose Monitoring
Hearing Aids
Therapeutics
Automotive
Driver Information and
Telematics
Powertrain
Safety and Chassis
Audio and Infotainment
Exterior & Interior Lighting
Body Electronics
Computing
&
Gaming
CPU / GPU Power Delivery
and Regulation
Efficient Power Supplies
Audio Signaling
Thermal Management
Portable Consumer
Display & Flash LED Lighting
Audio Subsystems
Data Switching
Battery Charging Control
Filtering for Camera and LCD
Interface
Media & Entertainment
Audio Signaling
Digital Audio/Video Transmission
Image Filtering
Digital Audio/Video Switching
Conditional Access Systems
Power Supply Efficiency
HV Communication
IP Cameras
World Class PoE
Surveillance Cameras
Industrial Ethernet
Robust Ethernet Environment
High Power Accuracy
Military & Aerospace
Guidance Systems
Infrared Imaging
Secure Military Communications
Commercial/Military Avionics
Tactical Missiles/Munitions


Employee
Presentation
July
2008
The Transformation Continues
Premier Energy
Efficient Supplier
FUTURE
Enhanced
Capabilities
Commodity/mass-market
orientation
Strong focus on operations /
supply chain / logistics
Sales focused on
procurement (transactional)
Strong service differentiation
Emerging design
relationships
Loose pricing management
Improving financial health
with debt and interest
expense reduction
1999-2004
Premier supplier of high
performance energy efficient
solutions
Customers Strategic
Semiconductor Supplier
Strong systems and field
applications
Revenues > $4 billion,
GMs > 50%
Alignment of resources across
company
Expansion of product, sales and
engineering capabilities through
acquisitions
Focused product success in high
growth applications
Important Supplier to Category One
and Category Two customers
Disciplined pricing process to
capture margin
Projected $2.2 billion in Sales and
40%+ GMs
Strong cash generation
Responsive and
Flexible Supplier
2004-2008


Employee
Presentation
July
2008
Product
Leadership
Customer
Intimacy
Operational
Excellence
Leveraging
our
operational
strengths.
Lower manufacturing costs.
Improve quality and supply chain.
Building intimate relationships with
market-making customers.
Dedicate resources to understand
the needs of our key customers.
Develop solutions for customer’s
key applications.
Improving our technological capabilities
to provide leadership in power and signal
management solutions.
Increase rate of technological innovation.
Shorten development cycle times.
ON Semiconductor Business Strategy


Employee
Presentation
July
2008
Together We Have A Winning Organization
Operational Excellence
Manufacturing
capability
to
deliver
solutions
at
the
right
value
point
Supply chain management expertise to ensure you get your parts when you want
them, where you want them, and how you want them
Customer Intimacy
Worldwide sales, design and support locations
Solution Engineering Centers dedicated to working closely with customers to drive
innovative designs with higher performance and getting them to market fast
Product Leadership
Expertise in power efficient products and solutions and memory technologies
Custom, integrated ASICs, EEPROM to standard components
Serving a broad range of end-market applications/end products
System knowledge to meet tomorrow’s power management challenges
Analog and power IC and memory design expertise to translate customer
requirements into next generation products
Broadest portfolio to offer both parts and system solutions


Employee
Presentation
July
2008
Operations Network


Employee
Presentation
July
2008
Worldwide Design


Employee
Presentation
July
2008
Why is ON Semiconductor Acquiring Catalyst
Semiconductor
About ON Semiconductor
Organization Overview and Common Questions
Expectations and FAQs
Employee Resources
Agenda


Employee
Presentation
July
2008
Custom and Foundry
Bob Klosterboer
Standard Products
Bill Hall
Catalyst Semiconductor
Gelu Voicu
President and
Chief Executive Officer
Keith Jackson
Finance
Donald Colvin
Integration
Charlotte Diener
COO –
Chief
Operating Officer
John Nelson
Sales & Marketing
Bob Mahoney
Human Resources
Colleen McKeown
General Counsel
Sonny Cave
Manufacturing Services
Bill George
Automotive and Power
Regulation Products
Andy Williams
Computing and
Digital and Consumer
Products
Bill Schromm
Organization


Employee
Presentation
July
2008
Common Questions
Organization Expectations
HR Policies
2008 Benefits
Travel
Policy
Payroll
Seniority
Vacation and sick leave


Employee
Presentation
July
2008
Why is ON Semiconductor Acquiring Catalyst
Semiconductor
About ON Semiconductor
Organization Overview and Common Questions
Expectations and FAQs
Employee Resources
Agenda


Employee
Presentation
July
2008
Expectations
Your manager should:
Hold department meetings
Help set your focus/priorities
Employees should:
Stay informed by reading FAQs from Catalyst Semiconductor
Ask questions
Send questions to employee.questions@onsemi.com


Employee
Presentation
July
2008
Expectations
Moving forward
You will see:
Ongoing communications
“The Circuit”
The employee newsletter
Updated FAQs
Ongoing communication meetings
Commitment to integrating work groups


Employee
Presentation
July
2008
Frequently Asked Questions
Top FAQs could be site-specific
1.
Where can I find answers to my questions?
2.
How many people are being laid off?
3.
Are layoffs planned?
4.
When will benefits change?
5.
When do I get paid?
6.
How will salaries be impacted?
7.
Will there be merit changes?
8.
Will my title change?


Employee
Presentation
July
2008
Why is ON Semiconductor Acquiring
Catalyst Semiconductor
About ON Semiconductor
Organization Overview and Common Questions
Expectations and FAQs
Employee Resources
Agenda


Employee
Presentation
July
2008
Colleen McKeown, SVP, HR and Communication
David Eichler, CFO/HR
Rosa Vasquez, HR
Kerry Chou, HR, Compensation
Mark Carr, VP, HR Operations
Tobin Cookman, HR Director
Robert Colbert, Manager,
Employee Communication
Linda Chan, HR Director Asia
employee.questions@onsemi.com
Human Resources Contacts


Employee
Presentation
July
2008
Company intranet
Site/department meetings
employee.questions@onsemi.com
Human Resources
Your leader
The Circuit –
the employee newsletter
Employee Resources


Employee
Presentation
July
2008
Questions?


Employee
Presentation
July
2008