Catalyst Semiconductor Debuts World's Smallest, Highest Efficiency Fractional Charge Pump.

Two New Additions to Catalyst's Innovative Quad-Mode(TM) LED Driver Product Line Deliver 10% Greater Efficiency(1) and Up to 65% Smaller Package

SANTA CLARA, Calif. -- Catalyst Semiconductor, Inc. (NASDAQ:CATS), a supplier of analog, mixed-signal and non-volatile memory semiconductors, continues to quickly take LED driver performance to new levels with the announcement of the CAT3643 three-channel and CAT3644 four-channel Quad-Mode(TM) charge pumps. The CAT3643 Quad-Mode charge pump is the world's smallest, highest efficiency charge pump, delivering 10 percent higher efficiency compared to three-mode charge pumps, in a 2.5mm x 2.5mm XQFN package with a 0.4mm profile. The CAT3643 drives up to three LEDs and comes just two months after Catalyst's launch of its groundbreaking Quad-Mode technology with the CAT3636 six-LED driver.

With the Quad-Mode switching architecture, the new CAT3643 and CAT3644 deliver efficiency levels as high as 92 percent, yet save significant board space and costs. The CAT3643 is the only charge pump available in an eXtra-thin 2.5mm x 2.5mm 12-lead XQFN package, with a 0.4mm profile, versus the traditional 3mm x 3mm 16-lead TQFN package and 0.8mm profile of most three-mode LED drivers.

The innovative, patent-pending Quad-Mode charge pump architecture delivers the high efficiency levels of inductor-based LED drivers, while eliminating the associated high-profile inductors, and unwanted EMI. Most charge pump LED drivers today offer three modes of operation corresponding to the ratio of the output voltage to the input voltage: 1x, 1.5x and 2x. The Quad-Mode architecture adds a fourth mode of operation, 1.33x, without the need for the additional capacitor and associated extra two pins required by all existing four-mode charge pumps, which enables the dramatically smaller, lower pin count XQFN package.

The 1.33x fractional operating mode also reduces the input switching currents seen at the battery, minimizing the overall supply noise - a critical parameter in portable devices such as cell phones. Additionally, by utilizing the 1.33x mode of operation, the excess boosted voltage is kept to a minimum, which reduces wasted power and subsequent device heat losses.

The XQFN package, reduced number of leads and high efficiency of the CAT3643 make it the world's lowest profile (0.4mm) and smallest size (65 percent smaller) fractional charge pump available.

According to Scott Brown, Vice President of Marketing for Catalyst Semiconductor, "The performance and space saving benefits of the CAT3643, combined with its eXtra-thin, low profile XQFN package provide an unprecedented performance alternative for designers of today's emerging, ultra-thin portable products. This device also addresses the 'sweet spot' of the portables market where 3-LEDs are becoming norm. Catalyst is proud to be in the unique position of giving designers a totally new LED driver alternative with the world's smallest profile and highest efficiency charge pump."

The CAT3643 includes fully featured LED programming and dimming control via Catalyst's flexible 1-wire EZDim[TM] programming interface. Six different current ratios are available via the EZDim interface.

Together with the CAT3643, Catalyst is also introducing the CAT3644 four-channel Quad-Mode device, which drives up to four LEDs, with efficiency levels as high as 92 percent.

CAT3643 and CAT3644 Product Features

--  Patent-pending Quad-Mode(TM) switching architecture

--  Fourth charge pump mode achieves 1.33x boost mode with only 2
    flying capacitors

--  Power efficiency up to 92 percent

--  Number of LEDs:
    CAT3643 -- 3 LEDs
    CAT3644 -- 4 LEDs

--  1-wire EZDim(TM) LED current programming

--  Packaging
    CAT3643:
    XQFN, 2.5mm x 2.5mm (0.4mm height), 12-lead
    TDFN, 3mm x 3mm, (0.8mm height), 12-lead
    TQFN, 3mm x 3mm (0.8mm height), 16-lead

    CAT3644:
    TQFN, 3mm x 3mm (0.8mm height), 16-lead

Price and Availability

Pricing for the CAT3643 in 10,000 piece quantities starts at $0.64 each. Pricing for 10,000 piece quantities of the CAT3644 is $0.68 each. Samples and evaluation kits are now available. Projected lead-times for production quantities are currently 6 to 8 weeks ARO.

[TABLE OMITTED]

About Catalyst Semiconductor

Founded in 1985, Catalyst Semiconductor, Inc. is headquartered in Santa Clara, California. The Company produces analog and mixed signal products in addition to an extensive range of non-volatile memories. The analog and mixed-signal product lines include Digitally Programmable Potentiometers [DPP(TM)], white and color LED drivers, DC/DC converters, voltage supervisors, linear regulators and I/O expanders. The memory product lines consist of serial and parallel EEPROMs, Flash and NVRAM. Catalyst devices are used in telecommunications, networking systems, computation, automotive, industrial and consumer markets. Typical applications include LCD displays, automotive instrumentation, optical networks, modems, wireless LANs, network cards, DIMM modules, cellular telephones, digital satellite box receivers, set-top boxes and Internet routers. Catalyst's Quality Management System is ISO 9001:2000 certified. All Catalyst products are available in "green" lead- and halogen-free versions with full RoHS compliance. For additional information about Catalyst Semiconductor, visit our website at: www.catsemi.com.

Forward-Looking Statements

Statements in this press release may be forward-looking statements that are subject to risks and uncertainties. These include, but are not limited to, references to lead times and product availability. Many factors can affect product availability, lead times and prices, including interruptions in our manufacturing processes and those of our foundries and other vendors, as well as the cyclicality of the semiconductor industry and customer demand. More information about factors that could cause actual results to differ materially from those in the forward-looking statements is contained under the section "Certain Factors That May Affect the Company's Future Results of Operations" listed from time-to-time in Catalyst's SEC reports including, but not limited to, the report on Form 10-K for the year ended April 30, 2006 and Form 10-Q for the second quarter of fiscal year 2007.

Editor Notes:

-- Trademark notices: Quad-Mode, EZDim and DPP are trademarks of Catalyst Semiconductor, Inc.

-- Electronic images are available at: www.catsemi.com/editor.

1Compared to three-mode charge pumps