This Management’s Discussion and Analysis of Financial Condition and Results of Operations includes a number of forward-looking statements, which reflect our current views with respect to future events and financial performance. In this report, the words “will”, “expects”, “believe”, “should”, “anticipate”, “if”, “future” and similar expressions identify forward-looking statements. Such statements are subject to certain risks and uncertainties, including our development efforts, the success of our product strategies, the maintenance of significant business relationships, as well as those discussed in the “Factors That May Affect Future Results of Operations” and elsewhere in this report. As a result of these risks, our actual results may differ materially from our historical or anticipated results. We caution you not to place undue reliance on these forward-looking statements, which speak only as of the date of this report.

The following management’s discussion and analysis of financial condition and results of operations should be read in conjunction with management’s discussion and analysis of financial condition and results of operations included in our Form 10-K for the year ended December 31, 2002.

Overview

We design, develop, manufacture and market proprietary, high-voltage, analog integrated circuits, or ICs, for use primarily in AC to DC and DC to DC power conversion markets. We have targeted high-volume power supply markets, including the communications, consumer, computer and industrial electronics markets. Our initial focus is on those applications that are sensitive to size, portability, energy efficiency and time-to-market. We introduced the TOPSwitch family of ICs in 1994 followed by an enhanced family of ICs, TOPSwitch-II, in April 1997. In September 1998, we announced the TinySwitch family of integrated circuits for power supplies used in a broad range of electronic products. TinySwitch ICs, which are designed to reduce standby energy by incorporating our new EcoSmart technology, enable a new class of light, compact, energy-efficient power supplies. In March 2000, we introduced the TOPSwitch-FX family of products, which also incorporates our EcoSmart technology to help engineers meet the growing need for environmentally friendly power solutions. In November 2000, we introduced the TOPSwitch-GX family of products. The GX family is capable of supplying output levels from 6 watts to 290 watts. In March 2001, we introduced the TinySwitch-II family of products with power levels ranging from 3 watts to 20 watts. In June 2002, we introduced DPA-Switch, which is a family of products that is the first highly integrated high-voltage power conversion IC designed specifically for use in DC-DC converters and distributed power architectures (DPAs). The four-device family covers a wide input voltage range of 16V to 75V, targeting 24 V/48V applications. In September 2002, we introduced LinkSwitch, which is an AC-DC power conversion IC specifically designed to replace linear transformers in the 0-3 watt range. The LinkSwitch family will enable electronics manufacturers to build smaller and more energy efficient power supplies for use in a large assortment of electronic products in the 0-3 watt range. All of our products introduced since 1998 incorporate our EcoSmart technology.

Critical Accounting Policies

We believe our critical accounting policies are as follows:

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. On an on-going basis, we evaluate our estimates, including those related to revenue recognition, sales returns, allowance for ship and debit, doubtful accounts receivables and inventories. We base our estimates on historical facts and various other assumptions that we believe to be reasonable at the time the estimates are made. Actual results could differ from those estimates.

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A brief description of these policies is set forth below.

Revenue recognition

Product revenues consist of sales to OEMs, merchant power supply manufacturers and distributors. Revenues from product sales to OEMs and merchant power supply manufacturers are recognized upon shipment. At that time, we provide for estimated sales returns and other allowances related to those sales. Between 50% and 65% of our sales are made to distributors under terms allowing certain rights of return and price protection for our products held in the distributors’ inventories. Therefore, we defer the recognition of revenue and the proportionate cost of revenues derived from sales to distributors until the distributors sell our products to their customers. We evaluate the amounts to defer based on the level of actual distributors’ inventory on hand as well as inventory that is in transit to the distributors. The gross profit that we defer as a result of this policy is reflected as “deferred income on sales to distributors” in the accompanying condensed consolidated balance sheets.

We have a wafer supply and technology license agreement with an unaffiliated wafer foundry. The wafer supply agreement, which expires in June 2005, is renewable. In connection with the technology license agreement, we are entitled to receive a royalty on the foundry’s sales of its own products that incorporate our technology. We recognize royalty revenue upon receipt of payment from the foundry.

Estimating sales returns and allowances

Net revenue consists of product revenue reduced by estimated sales returns and allowances. To estimate sales returns and allowances, we analyze, both when we initially establish the reserve, and then each quarter when we review the adequacy of the reserve, the following factors: historical returns, current economic trends, levels of inventories of our products held by our customers, and changes in customer demand and acceptance of our products. This reserve is reflected as a reduction to accounts receivable in the accompanying consolidated balance sheets. Increases to the reserve are recorded as a reduction to net revenue. Because the reserve for sales returns and allowances is based on our judgments and estimates, particularly as to future customer demand and acceptance of our products, our reserves may not be adequate to cover actual sales returns and other allowances. If our reserves are not adequate, our net revenues could be adversely affected.

Estimating ship and debit reserve

A large portion of our sales is made to distributors. Under certain circumstances, some of those sales are subject to credits that distributors claim on certain transactions and as protection against subsequent price declines on products they hold. The credits are referred to as “ship and debits.” The credits are available to the distributors after they have sold our products through to their end customer. We maintain a reserve for these credits that appears as a reduction to accounts receivable in our accompanying consolidated balance sheets. Any increase in the reserve results in a corresponding reduction in our net revenues. To establish the reserve and when we evaluate the adequacy of the reserve each quarter, we analyze historical ship and debit payments and levels of inventory in the distributor channels. If our reserves are not adequate, our net revenues could be adversely affected.

Estimating allowance for doubtful accounts

We maintain an allowance for losses we may incur as a result of our customers’ inability to make required payments. Any increase in the allowance results in a corresponding increase in our general and administrative expenses. In establishing this allowance, and then evaluating the adequacy of the allowance for doubtful accounts each quarter, we analyze historical bad debt, customer concentrations, customer credit-worthiness, current economic trends and changes in our customer payment terms. If the financial condition of one or more of our customers unexpectedly deteriorated, resulting in their inability to make payments, or if we otherwise underestimate the losses we incur as a result of our customers’ inability to pay us, we could be required to increase our allowance for doubtful accounts which could adversely affect our operating results.

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Estimating reserve for excess and obsolete inventory

We identify excess and obsolete products and analyze historical usage, forecasted production based on demand forecasts, current economic trends, and historical write-offs when evaluating the adequacy of the reserve for excess and obsolete inventory. This reserve is reflected as a reduction to inventory in the accompanying consolidated balance sheets, and an increase in cost of revenues. If actual market conditions are less favorable than our assumptions, we may be required to take additional reserves, which could adversely impact our cost of revenues and operating results.

Results of Operations

The following table sets forth certain operating data as a percentage of total net revenues for the periods indicated.

Comparison of the Three Months and Six Months Ended June 30, 2003 and 2002

Net revenues. Net revenues consist of revenues from product sales, which are calculated net of returns and allowances, plus license fees and royalties paid by licensees of our technology. Net revenues for the three months ended June 30, 2003 were $29.8 million compared to $27.1 million for the three months ended June 30, 2002, an increase of $2.7 million, or 9.8%. Net revenues for the six months ended June 30, 2003 were $58.9 million compared to $50.8 million for the comparable period of 2002, an increase of $8.1 million or 15.9%.

Net revenues from product sales represented $29.4 million and $26.9 million in the second quarter of 2003 and 2002, respectively. Net revenues from product sales represented $58.1 million and $50.3 million in the six months ended June 30, 2003 and 2002, respectively. The increase in net revenues from product sales for the three months and six months ended June 30, 2003 was driven primarily by increased sales of our products in the computer, consumer and industrial end markets. Sales increases were primarily from computer standby and LCD monitors in the computer market, set-top boxes, DVD players and home appliances in the consumer market and uninterruptible power supplies and motors in the industrial market. We expect our full year revenue mix for 2003, as a percentage of net revenues in the end markets which we serve, to be approximately 37% in the communications category, 27% in the consumer category, 23% in the computer category, 8% in the industrial electronics category and 5% in the other category. This compares to approximately 43% in the communications category, 23% in the consumer market category, 21% in the computer category, 6% in the industrial electronics category and 7% in the other category for the full year of 2002. We also expect the revenue mix of our product families for the full year of 2003 to be approximately 19% for TOPSwitch and TOPSwitch II, 28% for TOPSwitch FX and GX, 50% for TinySwitch and TinySwitch II, and 3% for our other products including our newest products LinkSwitch and DPA-Switch. This compares to approximately 33% for TOPSwitch and TOPSwitch II, 22% for TOPSwitch FX and GX, 44% for TinySwitch and TinySwitch II, and 1% for other products for the full year of 2002.

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International sales were $27.7 million in the second quarter of 2003 compared to $26.1 million for the same period in 2002, an increase of $1.6 million, or 6.4%, which represented 93.1% of net revenues compared to 96.0% in the comparable period of 2002. International sales were $55.1 million for the six months ended June 30, 2003 compared to $48.9 million for the same period in 2002, an increase of $6.2 million, or 12.7%, which represented 93.6% of net revenues compared to 96.3% in the comparable period of 2002. The increase in our international sales for the three months and six months ended June 30, 2003 was driven primarily by increased sales of our products in the computer, consumer and industrial end markets. Although the power supplies using our products are designed and distributed to end markets worldwide, most of these power supplies are manufactured in Asia. As a result, sales to this region were 81.3% and 83.6% of our product sales for the three months ended June 30, 2003 and 2002, respectively, and 81.5% and 82.0% of our product sales for the six months ended June 30, 2003 and 2002, respectively. We expect international sales to continue to account for a large portion of our net revenues.

Direct sales for the second quarter of 2003 were divided 63.2% to distributors and 36.8% to original equipment manufacturers, or OEMs, and power supply merchants, compared to 52.5% to distributors and 47.5% to OEMs and power supply merchants for the second quarter of 2002. For the six months ended June 30, 2003, direct sales were divided 61.3% to distributors and 38.7% to OEMs and power supply merchants, compared to 54.9% to distributors and 45.1% to OEMs and power supply merchants for the same period in 2002. For the three months ended June 30, 2003, sales to one customer accounted for 23.8% of net revenues, compared to 23.7% of net revenues for the three months ended June 30, 2002. A second customer accounted for 22.6% of net revenues for the three months ended June 30, 2003, compared to 13.9% for the three months ended June 30, 2002. Both of these customers are distributors. A third customer, who is an OEM, accounted for 14.4% of net revenues for the three months ended June 30, 2002 and accounted for less than 10% for the three months ended June 30, 2003. For the six months ended June 30, 2003, sales to the same two distributors accounted for 26.9% and 17.8% of net revenues, respectively, compared to 22.0% and 15.2% of net revenues, respectively, for the six months ended June 30, 2002. Sales to the same OEM, accounted for 14.0% of net revenues for the six months ended June 30, 2002 and accounted for less than 10% for the six months ended June 30, 2003. There were no other customers accounting for sales of more than 10% during the periods reported.

Cost of revenues; Gross profit. Gross profit is equal to net revenues less cost of revenues. Our cost of revenues consists primarily of costs associated with the purchase of wafers from Matsushita Electric Industrial Co, Ltd. (“Matsushita”), and with OKI Electric Industry (“OKI”), the assembly and packaging of our products, and internal labor and overhead associated with the testing of both wafers and packaged components. Gross profit for the second quarter of 2003 was $15.1 million, or 50.8% of net revenues, compared to $11.4 million, or 42.0% of net revenues for the same period in 2002. Gross profit for the six months ended June 30, 2003 was $30.2 million, or 51.3% of net revenues, compared to $21.7 million, or 42.7% of net revenues for the same period in 2002. The increase in gross profit percentage for the three months and six months ended June 30, 2003 was due primarily to improvements we made in our manufacturing costs which began in 2002 and have continued in 2003. We expect our gross profit percentage to be in a range of 49% to 50% for the full year of 2003; however, if pricing pressures from our customers increase during the year as a result of a continued economic slowdown or for other reasons, our gross profit could be lower.

Research and development expenses. Research and development expenses consist primarily of employee-related expenses, expensed material and facility costs associated with the development of new processes and new products. We also expense prototype wafers and mask sets related to new products as research and development costs until new products are released to production. Research and development expenses for the second quarter of 2003 were $4.2 million compared to $3.6 million for the same period in 2002, which represented 14.0% and 13.5% of our net revenues in each period, respectively. Research and development expenses for the six months ended June 30, 2003 were $8.3 million compared to $7.3 million for the same period in 2002, which represented 14.0% and 14.3% of our net revenues in each period, respectively. The increase in absolute dollars in research and development costs for the three months and six months ended June 30, 2003, was due primarily to increases in personnel costs associated with the hiring of additional employees over the same period in 2002. We expect research and development expenses to continue to increase in absolute dollars but depending on our ability to sell our products in the current economic environment, those expenses may fluctuate as a percentage of our net revenues.

Sales and marketing expenses. Sales and marketing expenses consist primarily of employee-related expenses, commissions to sales representatives and facilities expenses, including expenses associated with our regional sales offices and support offices. Sales and marketing expenses for the second quarter of 2003 were $3.9 million compared to $3.6

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million for the same period in 2002, which represented 13.2% and 13.4% of our net revenues in each period, respectively. Sales and marketing expenses for the six months ended June 30, 2003 were $8.0 million compared to $7.0 million for the same period in 2002, which represented 13.6% and 13.9% of our net revenues in each period, respectively. The increase in absolute dollars in sales and marketing expenses for the three months and six months ended June 30, 2003, was due primarily to increased personnel costs consisting of commissions, salaries and other related personnel costs. Included in the above marketing expenses are costs associated with applications engineering, which represented $900,000 in each of the three months ended June 30, 2003 and 2002, and $1.9 million and 1.8 million in the six months ended June 30, 2003 and 2002, respectively. We include applications engineering costs as part of sales and marketing expenses due to the fact that our products are generally incorporated into a customer’s power supply at the design stage. Our sales and marketing efforts are focused on facilitating the customer’s use of our products in the design of new power supplies for specific applications. An important competitive factor in determining whether a customer decides to use our products in its designs is our commitment to provide comprehensive application design support. We expect sales and marketing expenses to continue to increase in absolute dollars as we continue to expand our sales and marketing presence worldwide, but may fluctuate as a percentage of our net revenues.

General and administrative expenses. General and administrative expenses consist primarily of employee-related expenses for administration, finance, human resources and general management, as well as consulting fees, outside services, legal fees, auditing and tax services. For the quarters ended June 30, 2003 and 2002, general and administrative expenses were $1.8 million and $1.5 million, respectively, which represented 6.1% and 5.7% of our net revenues, respectively. For the six months ended June 30, 2003 and 2002, general and administrative expenses were $3.4 million and $3.0 million, respectively, which represented 5.8% of our net revenues in each period. The increase in spending for the comparable three and six-month periods was attributable primarily to increases in professional and legal expenses. Included in legal expenses are outside costs related to patents, which have been expensed as incurred, and we plan to continue with this policy in the future. We expect general and administrative expenses to increase in absolute dollars but depending on the sales levels we are able to achieve given current economic conditions, they may fluctuate as a percentage of our net revenues.

Other income, net. Other income, net, for the second quarter of 2003 decreased by $106, 000 compared to the same period in 2002. For the six months ended June 30, 2003, other income, net, decreased by $242,000 compared to the same period in 2002. The decrease for the three and six-month period ended June 30, 2003 was due primarily to lower interest rates on our cash equivalents and short-term investments in 2003 compared to 2002.

Provision for income taxes. Provision for income taxes represents Federal, state and foreign taxes. The provision for income taxes was $1.5 million for the second quarter of 2003 compared to $900,000 for the same period in 2002. The provision for income taxes was $3.1 million for the six months ended June 30, 2003 compared to $1.6 million for the same period in 2002. We adjusted our effective tax rate from 30% to 28% for the six months ended June 30, 2003 to reflect the expected tax rate for 2003. Our estimated effective tax rate used for 2002 was 30%. The difference between the statutory rate of 35% and our effective tax rate of 28% and 30% for the periods presented is due primarily to the beneficial impact of international sales, research and development credits and Federal tax-exempt investments.

Liquidity and Capital Resources

As of June 30, 2003, we had approximately $116.9 million in cash, cash equivalents and short-term investments, an increase of approximately $7.5 million from December 31, 2002. In addition, under a revolving line of credit with Union Bank of California, we can borrow up to $10.0 million. A portion of the credit line is used to cover advances for commercial letters of credit and standby letters of credit, which we provide to Matsushita and OKI, prior to the shipment of wafers by those foundries to us. As of June 30, 2003, there were outstanding letters of credit totaling approximately $4.7 million. The balance of this credit line was unused and available as of June 30, 2003. The line of credit agreement, which expires on July 1, 2004, contains financial covenants requiring that we maintain profitability on a quarterly basis and not pay or declare dividends without the bank’s prior consent. As of June 30, 2003, we were in compliance with these financial covenants. We have previously financed a significant portion of our machinery and equipment through capital equipment leases. As of June 30, 2003, we owed approximately $154,000 on our various capital equipment leases. There was no additional equipment financing during the six months ended June 30, 2003.

As of June 30, 2003, we had working capital, defined as current assets less current liabilities, of approximately $137.4 million, an increase of approximately $17.0 million from December 31, 2002. Our operating activities generated cash of $4.7 million and $17.3 million in the six months ended June 30, 2003 and 2002, respectively. Cash generated in the first six months of 2003 was principally the result of net income in the amount of $8.1 million, depreciation and

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amortization of $3.4 million and the tax benefit associated with employee stock plans of $2.7 million, partially offset by increases in inventory of $5.0 million and accounts receivable of $3.0 million and decrease in accounts payable of $1.9 million. Cash generated in the first six months of 2002 was principally the result of net income in the amount of $3.7 million, depreciation and amortization of $3.3 million, tax benefit associated with employee stock plans of $1.4 million, decrease in inventory of $9.6 million and an increase in accrued liabilities of $1.9 million, partially offset by an increase in accounts receivable of $3.3 million.

Our investing activities were net proceeds of $11.0 million in the six months ended June 30, 2003 from maturities of short-term investments, and net purchases of short-term investments of $20.9 million in the six months ended June 30, 2002. Purchases of property and equipment were $5.1 million and $815,000 in the six months ended June 30, 2003 and 2002, respectively. Our financing activities were primarily receipts from the issuance of common stock through the exercise of stock options and purchases through our employee stock purchase plan of $8.0 million and $3.3 million in the six months ended June 30, 2003 and 2002, respectively, offset by payments for capitalized lease obligations of $120,000 and $322,000 in the six months ended June 30, 2003 and 2002, respectively.

In April 2003, we entered into a contract to purchase our current San Jose facilities for approximately $30.0 million. A $3.0 million deposit was made in April 2003. We expect the purchase to close by the end of the third quarter of 2003, and anticipate that we will fund the purchase price from cash and working capital.

During the first six months of 2003, a significant portion of our cash flow was generated by our operations. If our operating results deteriorate during the remainder of 2003, as a result of decrease in customer demand, or severe pricing pressures from our customers or our competitors, or for other reasons, our ability to generate positive cash flow from operations may be jeopardized. In that case, we may be forced to use our cash, cash equivalents and short-term investments, or seek financing from third parties to fund our operations. We believe that cash generated from operations, together with existing sources of liquidity, will satisfy our projected working capital and other cash requirements for at least the next 12 months.

Recent Accounting Pronouncements

In January 2003, the Financial Accounting Standards Board issued FASB Interpretation No. 46, “Consolidation of Variable Interest Entities,” which addresses consolidation by a business of variable interest entities in which it is the primary beneficiary. The Interpretation is effective immediately for certain disclosure requirements and variable interest entities created after January 31, 2003, and in fiscal 2004 for all other variable interest entities. We have reviewed the provisions of the Interpretation and have determined that we have no variable interest entities, consequently there was no impact on our consolidated financial statements.

Effective prospectively for arrangements entered into in fiscal periods beginning after June 15, 2003, Emerging Issues Task Force (“EITF”) Issue 00-21, “Revenue Arrangements with Multiple Deliverables,” addresses the accounting, by a vendor, for contractual arrangements in which multiple revenue-generating activities will be performed by the vendor. In some situations, the different revenue-generating activities (deliverables) are sufficiently separable and there exists sufficient evidence of fair values to account separately for the different deliverables (that is, there are separate units of accounting). In other situations, some or all of the different deliverables are interrelated closely or there is not sufficient evidence of fair value to account separately for the different deliverables. EITF Issue 00-21 addresses when and, if so, how an arrangement involving multiple deliverables should be divided into separate units of accounting. We do not expect the adoption of EITF Issue 00-21 to have a material impact on our consolidated financial statements.

In April 2003, the FASB issued SFAS No. 149, “Amendments of Statement 133 on Derivative Instruments and Hedging Activities,” which amends and clarifies financial accounting and reporting for derivative instruments, including certain derivative instruments embedded in other contracts and for hedging activities under SFAS No. 133. This statement is effective for contracts entered into or modified after June 30, 2003, with certain exceptions, and for hedging relationships designated after June 30, 2003. Since we do not use derivative instruments or engage in hedging activities, we do not expect the adoption of SFAS No. 149 to have a material impact on our consolidated financial statements.

In May 2003, the FASB issued SFAS No. 150, “Accounting for Certain Financial Instruments with Characteristics of Both Liabilities and Equity,” which establishes standards for how an issuer classifies and measures certain financial instruments with characteristics of both liabilities and equity. Financial instruments that are within the scope of the statement, which previously were often classified as equity, must now be classified as liabilities. This statement is effective for financial instruments entered into or modified after May 31, 2003, and otherwise shall be effective at the beginning of the first interim period beginning after June 15, 2003. We do not expect the adoption of SFAS No. 150 to have a material impact on our consolidated financial statements.

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Factors That May Affect Future Results of Operations

In addition to the other information in this report, the following factors should be considered carefully in evaluating our business before purchasing shares of our stock.

Our quarterly operating results are volatile and difficult to predict. If we fail to meet the expectations of public market analysts or investors, the market price of our common stock may decrease significantly . Our net revenues and operating results have varied significantly in the past, are difficult to forecast, are subject to numerous factors both within and outside of our control, and may fluctuate significantly in the future. As a result, our quarterly operating results could fall below the expectations of public market analysts or investors. If that occurs, the price of our stock may decline.

Some of the factors that could affect our operating results include the following:

We do not have long-term contracts with any of our customers and if they fail to place, or if they cancel or reschedule orders for our products, our operating results and business may suffer . Our business is characterized by short-term customer orders and shipment schedules. The ordering patterns of some of our existing large customers have been unpredictable in the past, and we expect that customer-ordering patterns will continue to be unpredictable in the future. Not only does the volume of units ordered by particular customers vary substantially from period to period, but also purchase orders received from particular customers often vary substantially from early oral estimates provided by those customers for planning purposes. In addition, customer orders can be canceled or rescheduled without significant penalty to the customer. In the past we have experienced customer cancellations of substantial orders for reasons beyond our control, and significant cancellations could occur again at any time.

Intense competition in the high-voltage power supply industry may lead to a decrease in the average selling price and reduced sales volume of our products, which may harm our business . The high-voltage power supply industry is intensely competitive and characterized by significant price erosion. Our products face competition from alternative technologies, including traditional linear transformers and discrete switcher power supplies. If the price of competing products decreases significantly, the cost effectiveness of our products will be adversely affected. If power requirements for applications in which our products are currently utilized go outside the cost effective range of our products, these older alternative technologies can be used more cost effectively. We cannot assure you that our products will continue to compete favorably or that we will be successful in the face of increasing competition from new products and enhancements introduced by existing competitors or new companies entering this market. We believe our failure to compete successfully in the high-voltage power supply business, including our ability to introduce new products with higher average selling prices, would materially harm our operating results.

If demand for our products declines in the major end markets that we serve, our net revenues will decrease . Applications of our products in the consumer, communications and computer end markets, such as cellular phone chargers, stand-by power supplies for PCs, power supplies for TV set top boxes and power supplies for home appliances have and will continue to account for a large percentage of our net revenues. We expect that a significant level of our net revenues and operating results will continue to be dependent upon these applications in the near term. The demand for these

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products has been highly cyclical and has been subject to significant economic downturns at various times. Announcements of economic slowdown by major companies in any of the end markets we serve, could indirectly through our customers, cause a slowdown in demand for some of our ICs. When our customers are not successful in maintaining high levels of demand for their products, their demand for our ICs decreases, which adversely affects our operating results. Any significant downturn in demand in these markets would cause our net revenues to decline and could cause the price of our stock to fall.

Because the sales cycle for our products can be lengthy, we may incur substantial expenses before we generate significant revenues, if any . Our products are generally incorporated into a customer’s products at the design stage. However, customer decisions to use our products, commonly referred to as design wins, which can often require us to expend significant research and development and sales and marketing resources without any assurance of success, often precede volume sales, if any, by a year or more. The value of any design win will largely depend upon the commercial success of the customer’s product. We cannot assure you that we will continue to achieve design wins or that any design win will result in future revenues. If a customer decides at the design stage not to incorporate our products into its product, we may not have another opportunity for a design win with respect to that product for many months or years.

Our products must meet exacting specifications, and undetected defects and failures may occur which may cause customers to return or stop buying our products . Our customers generally establish demanding specifications for quality, performance and reliability that our products must meet. ICs as complex as those we sell often encounter development delays and may contain undetected defects or failures when first introduced or after commencement of commercial shipments. We have from time to time in the past experienced product quality, performance or reliability problems. If defects and failures occur in our products, we could experience lost revenue, increased costs, including warranty expense and costs associated with customer support, delays in or cancellations or rescheduling of orders or shipments and product returns or discounts, any of which would harm our operating results.

Our international sales activities account for a substantial portion of our net revenues and subject us to substantial risks . Sales to customers outside of the United States account for a large portion of our net revenues, including approximately 94% and 96% of our net revenues in the six months ended June 30, 2003 and 2002, respectively. If our international sales declined and we were unable to increase domestic sales, our revenues would decline and our operating results would be harmed. International sales involve a number of risks to us, including:

Our failure to adequately address these risks could reduce our international sales, which would materially adversely affect our operating results. Furthermore, because substantially all of our foreign sales are denominated in U.S. dollars, increases in the value of the dollar increase the price in local currencies of our products in foreign markets and make our products relatively more expensive and less price competitive than competitors’ products that are priced in local currencies.

We depend on third-party suppliers to provide us with wafers for our products and if they fail to provide us sufficient wafers, our business will suffer . We have a supply arrangement for the production of wafers with Matsushita, which expires in June 2005, and with OKI, which expires in April 2008. Although certain aspects of our relationships with Matsushita and OKI are contractual, many important aspects of these relationships depend on their continued cooperation. We cannot assure you that we will continue to work successfully with Matsushita or OKI in the future, that they will continue to provide us with sufficient capacity at their foundries to meet our needs, or that either of them will not seek an early termination of its wafer supply agreement with us. Any serious disruption in the supply of wafers from either OKI or Matsushita would harm our business. We estimate that it would take 9 to 12 months from the time we identified an alternate manufacturing source before that source could produce wafers with acceptable manufacturing yields in sufficient quantities to meet our needs. In May of 2003, we signed a wafer supply agreement with a third foundry, ZMD Analog Mixed Signal Services GmbH & CoKG (ZMD). ZMD is located in Germany and is expected to be able to produce wafers for us by the end of 2004. Our agreement with ZMD expires on December 31, 2009.

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Although we provide Matsushita and OKI with rolling forecasts of our production requirements, their ability to provide wafers to us is limited by the available capacity of the foundry in which they manufacture wafers for us. An increased need for capacity to meet internal demands or demands of other customers could cause Matsushita and OKI to reduce capacity available to us. Matsushita and OKI may also require us to pay amounts in excess of contracted or anticipated amounts for wafer deliveries or require us to make other concessions in order to acquire the wafer supply necessary to meet our customers’ requirements. Any of these concessions could harm our business.

If our third-party suppliers and independent subcontractors do not produce our wafers and assemble our finished products at acceptable yields, our net revenues may decline. We depend on Matsushita and OKI to produce wafers, and independent subcontractors to assemble finished products, at acceptable yields and to deliver them to us in a timely manner. The failure of Matsushita or OKI to supply us wafers at acceptable yields could prevent us from selling our products to our customers and would likely cause a decline in our net revenues. In addition, our IC assembly process requires our manufacturers to use a high-voltage molding compound available from only one vendor, which is difficult to process. This compound and its required processes, together with the other non-standard materials and processes needed to assemble our products, require a more exacting level of process control than normally required for standard packages. Unavailability of the sole source compound or problems with the assembly process can materially adversely affect yields and cost to manufacture. We cannot assure you that acceptable yields will be maintainable in the future.

Matsushita has licenses to our technology, which it may use to our detriment . Our ability to take advantage of the potentially large Japanese market for our products is largely dependent on Matsushita and its ability to promote and deliver our products. Pursuant to our agreement with Matsushita, Matsushita has the right to manufacture and sell products using our technology to Japanese companies worldwide and to subsidiaries of Japanese companies located in Asia. Although we receive royalties on Matsushita’s sales, these royalties are substantially lower than the gross profit we receive on direct sales. We cannot assure you that Matsushita will not use the technology rights we have granted it to develop or market competing products following any termination of its relationship with us or after termination of Matsushita’s royalty obligation to us.

If our efforts to enhance existing products and introduce new products are not successful, we may not be able to generate demand for our products. Our success depends in significant part upon our ability to develop new ICs for high-voltage power conversion for existing and new markets, to introduce these products in a timely manner and to have these products selected for design into products of leading manufacturers. New product introduction schedules are subject to the risks and uncertainties that typically accompany development and delivery of complex technologies to the market place, including product development delays and defects. If we fail to develop and sell new products in a timely manner, our net revenues could decline.

We cannot be sure that we will be able to adjust to changing market demands as quickly and cost-effectively as necessary to compete successfully. Furthermore, we cannot assure you that we will be able to introduce new products in a timely and cost-effective manner or in sufficient quantities to meet customer demand or that these products will achieve market acceptance. Our failure, or our customers’ failure to develop and introduce new products successfully and in a timely manner would harm our business and may cause the price of our common stock to fall. In addition, customers may defer or return orders for existing products in response to the introduction of new products. Although we maintain reserves for potential customer returns, we cannot assure you that these reserves will be adequate.

If our products do not penetrate additional markets, our business will not grow as we predict. We believe that our future success depends in part upon our ability to penetrate additional markets for our products. We cannot assure you that we will be able to overcome the marketing or technological challenges necessary to do so. To the extent that a competitor penetrates additional markets before we do, or takes market share from us in our existing markets, our net revenues and financial condition could be materially adversely affected.

In the event of an earthquake, terrorist act or other disaster, our operations may be interrupted and our business would be harmed. Our principal executive offices and operating facilities situated near San Francisco, California, and our major suppliers (foundries and assembly houses) all situated in the Far East, are all located in areas that have been subject to severe earthquakes. In the event of an earthquake, we and/or our major suppliers may be temporarily unable to continue operations and may suffer significant property damage. Any such interruption in our ability or that of our major suppliers to continue operations at our facilities could delay the development and shipment of our products.

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Like other U.S. companies, our business and operating results are subject to uncertainties arising out of the recent terrorist attacks on the United States, including the potential worsening or extension of the current global economic slowdown, the economic consequences of current and potential military actions or additional terrorist activities and associated political instability, and the impact of heightened security concerns on domestic and international travel and commerce. Such uncertainties could also lead to delays or cancellations of customer orders, a general decrease in corporate spending or our inability to effectively market and sell our products. Any of these results could substantially harm our business and results of operations, causing a decrease in our revenues.

The recent outbreak of Severe Acute Respiratory Syndrome (SARS) may adversely impact the operations of our major suppliers and our global operations. In 2003, there has been an outbreak of Severe Acute Respiratory Syndrome (SARS). At the time of this 10-Q filing, the outbreak has been largely concentrated in Asia, although cases have been confirmed in, among other locations, the United States and Canada. SARS could have an adverse impact on our major suppliers, which are located in Asia, resulting in a serious disruption in the supply of wafers and subsequent harm to our business. We estimate that it would take 9 to 12 months from the time we identified an alternate manufacturing source before that source could produce wafers with acceptable manufacturing yields in sufficient quantities to meet our needs. SARs could also have an impact on the end market demand for consumer products that incorporate our chips. If the number of cases continues to rise or spread to other locations, our global sales and operations could be harmed.

If we are unable to adequately protect or enforce our intellectual property rights, we could lose market share, incur costly litigation expenses or lose valuable assets. Our success depends upon our ability to protect our intellectual property, including patents, trade secrets, and know-how, and to continue our technological innovation. We cannot assure you that the steps we have taken to protect our intellectual property will be adequate to prevent misappropriation or that others will not develop competitive technologies or products. From time to time we have received, and we may receive in the future, communications alleging possible infringement of patents or other intellectual property rights of others. Litigation, which could result in substantial cost to us, may be necessary to enforce our patents or other intellectual property rights or to defend us against claimed infringement of the rights of others. The failure to obtain necessary licenses or other rights or litigation arising out of infringement claims could cause us to lose market share and harm our business.

Moreover, the laws of some foreign countries in which our technology is or may in the future be licensed may not protect our intellectual property rights to the same extent as the laws of the United States, thus increasing the possibility of infringement of our intellectual property.

We must attract and retain qualified personnel to be successful and competition for qualified personnel is intense in our market. Our success depends to a significant extent upon the continued service of our executive officers and other key management and technical personnel, and on our ability to continue to attract, retain and motivate qualified personnel, such as experienced analog design engineers and systems applications engineers. The competition for these employees is intense, particularly in Silicon Valley. The loss of the services of one or more of our engineers, executive officers or other key personnel or our inability to recruit replacements for these individuals or to otherwise attract, retain and motivate qualified personnel could harm our business. We do not have long-term employment contracts with, and we do not have in place key person life insurance policies on, any of our employees.

We have adopted anti-takeover measures, which may make it more difficult for a third party to acquire us . Our board of directors has the authority to issue up to 3,000,000 shares of preferred stock and to determine the price, rights, preferences and privileges of those shares without any further vote or action by the stockholders. The rights of the holders of common stock will be subject to, and may be adversely affected by, the rights of the holders of any preferred stock that may be issued in the future. The issuance of shares of preferred stock, while potentially providing flexibility in connection with possible acquisitions and for other corporate purposes, could have the effect of making it more difficult for a third party to acquire a majority of our outstanding voting stock. We have no present intention to issue shares of preferred stock.

In addition, our board of directors has adopted a Preferred Stock Purchase Rights Plan intended to guard against hostile takeover tactics. The existence of this plan could have the effect of making it more difficult for a third party to acquire a majority of our outstanding voting stock.

The future trading price of our common stock could be subject to wide fluctuations in response to a variety of factors . The price of our common stock has been, and is likely to be, volatile. Factors including future announcements concerning us, our customers or our competitors, quarterly variations in operating results, announcements of technological innovations, the introduction of new products or changes in our product pricing policies or those of our competitors, proprietary rights or other litigation, changes in earnings estimates by analysts and other factors could cause the market

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price of our common stock to fluctuate substantially. In addition, stock prices for many technology companies fluctuate widely for reasons, which may be unrelated to operating results. These fluctuations, as well as general economic, market and political conditions may harm the market price of our common stock.

Recently enacted and proposed changes in securities laws and regulations are likely to increase our costs . The Sarbanes-Oxley Act of 2002 that became law in July 2002 requires changes in some of our corporate governance practices. The Act also requires the Securities and Exchange Commission to promulgate new rules on a variety of subjects. In addition to final rules and rule proposals already made by the Securities and Exchange Commission, Nasdaq has proposed revisions to its requirements for companies that are Nasdaq-listed. We expect these new rules and regulations to increase our legal and financial compliance costs, and to make some activities more difficult, time consuming and/or costly. We also expect these new rules and regulations to make it more expensive for us to obtain director and officer liability insurance, and we may be required to accept reduced coverage or incur substantially higher costs to obtain coverage. These new rules and regulations could also make it more difficult for us to attract and retain qualified members of our board of directors, particularly to serve on our audit committee, and qualified executive officers.

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