ALPHA & OMEGA SEMICONDUCTOR LTD, 10-Q filed on 11/7/2014
Quarterly Report
Document and Entity Information
3 Months Ended
Sep. 30, 2014
Oct. 31, 2014
Entity Information [Line Items]
 
 
Entity Registrant Name
ALPHA & OMEGA SEMICONDUCTOR Ltd 
 
Entity Central Index Key
0001387467 
 
Current Fiscal Year End Date
--06-30 
 
Entity Filer Category
Accelerated Filer 
 
Document Type
10-Q 
 
Document Period End Date
Sep. 30, 2014 
 
Document Fiscal Year Focus
2015 
 
Document Fiscal Period Focus
Q1 
 
Amendment Flag
false 
 
Entity Common Stock, Shares Outstanding
 
26,451,629 
CONDENSED CONSOLIDATED BALANCE SHEETS (USD $)
In Thousands, unless otherwise specified
Sep. 30, 2014
Jun. 30, 2014
Current assets:
 
 
Cash and cash equivalents
$ 117,834 
$ 117,788 
Restricted cash
366 
244 
Accounts receivable, net
35,066 
36,535 
Inventories
68,410 
66,560 
Deferred income tax assets
1,423 
2,842 
Other current assets
3,873 
3,810 
Total current assets
226,972 
227,779 
Property, plant and equipment, net
120,899 
123,254 
Intangible assets, net
66 
229 
Goodwill
269 
269 
Deferred income tax assets-long term
10,931 
10,854 
Other long-term assets
2,283 
1,963 
Total assets
361,420 
364,348 
Current liabilities:
 
 
Short term debt
7,857 
13,821 
Accounts payable
40,487 
38,760 
Accrued liabilities
17,277 
17,376 
Income taxes payable
2,384 
1,933 
Deferred margin
745 
665 
Capital leases
1,051 
1,061 
Total current liabilities
69,801 
73,616 
Income taxes payable - long term
2,336 
2,315 
Deferred income tax liabilities
1,947 
3,234 
Capital leases - long term
779 
1,005 
Other long term liabilities
1,099 
1,143 
Total liabilities
75,962 
81,313 
Commitments and contingencies (Note 9)
   
   
Preferred shares, par value $0.002 per share:
 
 
Authorized: 10,000 shares, issued and outstanding: none at September 30, 2014 and June 30, 2014
0 
0 
Common shares, par value $0.002 per share:
 
 
Authorized: 50,000 shares, issued and outstanding: 26,786 shares and 26,446 shares at September 30, 2014 and 26,644 shares and 26,304 shares at June 30, 2014
54 
53 
Treasury shares at cost, 340 shares at September 30, 2014 and 340 shares at June 30, 2014
(2,889)
(2,889)
Additional paid-in capital
175,990 
174,084 
Accumulated other comprehensive income
985 
1,033 
Retained earnings
111,318 
110,754 
Total shareholders’ equity
285,458 
283,035 
Total liabilities and shareholders’ equity
$ 361,420 
$ 364,348 
CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)
Sep. 30, 2014
Jun. 30, 2014
Common shares, par value (in dollars per share)
$ 0.002 
$ 0.002 
Common shares, authorized (in shares)
50,000,000 
50,000,000 
Common stock, shares issued (in shares)
26,786,000 
26,644,000 
Common stock, shares outstanding (in shares)
26,446,000 
26,304,000 
Preferred stock, par value (in dollars per share)
$ 0.002 
$ 0.002 
Preferred stock, shares authorized (in shares)
10,000,000 
10,000,000 
Preferred stock, shares issued (in shares)
0 
0 
Preferred stock, shares outstanding (in shares)
0 
0 
Treasury shares (in shares)
340,000 
340,000 
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $)
In Thousands, except Per Share data, unless otherwise specified
3 Months Ended
Sep. 30, 2014
Sep. 30, 2013
Revenue
$ 88,217 
$ 84,121 
Cost of goods sold
70,057 
66,970 
Gross profit
18,160 
17,151 
Operating expenses
 
 
Research and development
6,796 
6,847 
Selling, general and administrative
9,604 
8,940 
Total operating expenses
16,400 
15,787 
Operating income
1,760 
1,364 
Interest income and other, net
48 
24 
Interest expense
(73)
(79)
Income before income taxes
1,735 
1,309 
Income tax expense
1,171 
1,002 
Net income
$ 564 
$ 307 
Net income per share
 
 
Basic (in dollars per share)
$ 0.02 
$ 0.01 
Diluted (in dollars per share)
$ 0.02 
$ 0.01 
Weighted average number of common shares used to compute net income per share
 
 
Basic (in shares)
26,385 
25,684 
Diluted (in shares)
27,003 
26,309 
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $)
In Thousands, unless otherwise specified
3 Months Ended
Sep. 30, 2014
Sep. 30, 2013
Net income
$ 564 
$ 307 
Foreign currency translation adjustment
(48)
54 
Total comprehensive income
$ 516 
$ 361 
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)
In Thousands, unless otherwise specified
3 Months Ended
Sep. 30, 2014
Sep. 30, 2013
Cash flows from operating activities
 
 
Net income
$ 564 
$ 307 
Adjustments to reconcile net income to net cash provided by operating activities:
 
 
Depreciation
6,955 
6,927 
Amortization
91 
103 
Allowance for doubtful accounts
0 
(363)
Share-based compensation expense
1,102 
1,209 
Deferred income taxes, net
54 
378 
(Gain) loss on disposal of property and equipment
22 
(74)
Forgiveness of loan
(250)
0 
Changes in assets and liabilities:
 
 
Accounts receivable
1,469 
(2,288)
Inventories
(1,849)
(83)
Other current and long-term assets
(383)
(541)
Accounts payable
(515)
712 
Income taxes payable
472 
(451)
Accrued and other liabilities
(103)
904 
Net cash provided by operating activities
7,629 
6,740 
Cash flows from investing activities
 
 
Purchases of property and equipment
(2,345)
(1,578)
Proceeds from sale of property and equipment
0 
194 
Restricted cash placed
(122)
(42)
Net cash used in investing activities
(2,467)
(1,426)
Cash flows from financing activities
 
 
Proceeds from exercise of stock options
858 
23 
Repayments of borrowings
(5,714)
(1,429)
Principal payments on capital leases
(237)
(333)
Net cash used in financing activities
(5,093)
(1,739)
Effect of exchange rate changes on cash and cash equivalents
(23)
14 
Net increase in cash and cash equivalents
46 
3,589 
Cash and cash equivalents at beginning of period
117,788 
92,406 
Cash and cash equivalents at end of period
117,834 
95,995 
Supplemental disclosures of non-cash investing and financing information:
 
 
Property and equipment purchased but not yet paid
5,594 
2,157 
Re-issuance of treasury stock
$ 0 
$ 4 
The Company and Significant Accounting Policies
The Company and Significant Accounting Policies
The Company and Significant Accounting Policies
The Company
Alpha and Omega Semiconductor Limited and its subsidiaries (the “Company,” "AOS," "we" or "us") design, develop and supply a broad range of power semiconductors. The Company's portfolio of products targets high-volume applications, including portable computers, flat panel TVs, LED lighting, smart phones, battery packs, consumer and industrial motor controls and power supplies for TVs, computers, servers and telecommunications equipment. The Company conducts its operations primarily in the United States of America (“USA”), Hong Kong, Macau, China, Taiwan, Korea and Japan.
Basis of Preparation
The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) for interim financial information and with the instructions to Article 10 of Securities and Exchange Commission Regulation S-X, as amended. They do not include all information and footnotes necessary for a fair presentation of financial position, results of operations and cash flows in conformity with U.S. GAAP for complete financial statements. These condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and related notes contained in the Company’s Annual Report on Form 10-K for the fiscal year ended June 30, 2014. All significant intercompany balances and transactions have been eliminated in consolidation. In the opinion of management, all adjustments (consisting of normal recurring adjustments and accruals) considered necessary for a fair presentation of the results of operations for the period presented have been included in the interim periods. Operating results for the three months ended September 30, 2014 are not necessarily indicative of the results that may be expected for the fiscal year ending June 30, 2015. The condensed consolidated balance sheet at June 30, 2014 is derived from the audited financial statements included in the Company’s Annual Report on Form 10-K for the fiscal year ended June 30, 2014.
Use of Estimates
The preparation of the condensed consolidated financial statements in conformity with U.S. GAAP requires the Company to make estimates, judgments and assumptions that affect the reported amounts of assets, liabilities, revenue and expenses. To the extent there are material differences between these estimates and actual results, the Company's condensed consolidated financial statements will be affected. On an ongoing basis, the Company evaluates the estimates, judgments and assumptions including those related to stock rotation returns, price adjustments, allowance for doubtful accounts, inventory reserves, warranty accrual, income taxes, share-based compensation, and useful lives for property, plant and equipment and intangible assets.
Fair Value of Financial Instruments
The fair value of cash equivalents are based on observable market prices and have been categorized in Level 1 in the fair value hierarchy. Cash equivalents consist primarily of short term bank deposits. The carrying values of financial instruments such as cash and cash equivalents, accounts receivable and accounts payable approximate their carrying values due to their short-term maturities. The carrying value of the Company's debt is considered a reasonable estimate of fair value which is estimated by considering the current rates available to the Company for debt of the same remaining maturities, structure and terms of the debts.
Comprehensive Income (Loss)
Comprehensive income (loss) is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources. The Company's accumulated other comprehensive income (loss) consists of cumulative foreign currency translation adjustments. Total comprehensive income (loss) is presented in the condensed consolidated statements of comprehensive income (loss).
Recent Accounting Pronouncements
    
In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (“ASU 2014-09”). The standard provides companies with a single model for use in accounting for revenue arising from contracts with customers and supersedes current revenue recognition guidance, including industry-specific revenue guidance. The core principle of the model is to recognize revenue when control of the goods or services transfers to the customer, as opposed to recognizing revenue when the risks and rewards transfer to the customer under the existing revenue guidance. ASU 2014-09 is effective for annual reporting periods beginning after December 15, 2016. Early adoption is not permitted. The guidance permits companies to either apply the requirements retrospectively to all prior periods presented, or apply the requirements in the year of adoption, through a cumulative adjustment. The Company is in the process of evaluating the impact of adoption on its consolidated financial statements.
Net Income Per Share
Net Income Per Share
Net Income Per Share
The following table presents the calculation of basic and diluted net income per share:
 
Three Months Ended September 30,
 
2014
 
2013
 
(in thousands, except per share data)
Numerator:
 
 
 
Net income
$
564

 
$
307

 
 
 
 
Denominator:
 
 
 
Basic:
 
 
 
Weighted average number of common shares used to compute basic net income per share
26,385

 
25,684

Diluted:
 
 
 
Weighted average number of common shares used to compute basic net income per share
26,385

 
25,684

Effect of potentially dilutive securities:
 
 
 
Stock options, RSUs and ESPP shares
618

 
625

Weighted average number of common shares used to compute diluted net income per share
27,003

 
26,309

Net income per share:
 
 
 
Basic
$
0.02

 
$
0.01

Diluted
$
0.02

 
$
0.01


The following potential dilutive securities were excluded from the computation of diluted net income per share as their effect would have been anti-dilutive:
 
Three Months Ended September 30,
 
2014
 
2013
 
(in thousands)
Employee stock options and RSUs
2,393

 
2,783

ESPP to purchase common shares
—

 
307

Total potential dilutive securities
2,393

 
3,090

Concentration of Credit Risk and Significant Customers
Concentration of Credit Risk and Significant Customers
Concentration of Credit Risk and Significant Customers
The Company manages its credit risk associated with exposure to distributors and direct customers on outstanding accounts receivable through the application of credit approvals, credit ratings and other monitoring procedures. In some instances, the Company also obtains letters of credit from certain customers.
Credit sales, which are mainly on credit terms of 30 to 60 days, are only made to customers who meet the Company's credit requirements, while sales to new customers or customers with low credit ratings are usually made on an advance payment basis. The Company considers its trade accounts receivable to be of good credit quality because its key distributors and direct customers have long-standing business relationships with the Company and the Company has not experienced any significant bad debt write-offs of accounts receivable in the past. The Company closely monitors the aging of accounts receivable from its distributors and direct customers, and regularly reviews their financial positions, when available.
Summarized below are individual customers whose revenue or accounts receivable balances were 10% or higher than the respective total consolidated amounts:
 
Three Months Ended September 30,
Percentage of revenue
2014
 
2013
Customer A
24.1
%
 
20.6
%
Customer B
39.6
%
 
44.3
%
Customer C
12.9
%
 
11.8
%

 
September 30,
2014
 
June 30,
2014
Percentage of accounts receivable
 
Customer A
32.6
%
 
23.1
%
Customer B
15.6
%
 
30.5
%
Customer C
24.7
%
 
17.4
%
Balance Sheet Components
Balance Sheet Components
Balance Sheet Components
Accounts receivable:
 
September 30,
2014
 
June 30,
2014
 
(in thousands)
Accounts receivable
$
50,657

 
$
51,128

Less: Allowance for price adjustments
(15,561
)
 
(14,563
)
Less: Allowance for doubtful accounts
(30
)
 
(30
)
Accounts receivable, net
$
35,066

 
$
36,535



Inventories:
 
September 30,
2014
 
June 30,
2014
 
(in thousands)
Raw materials
$
18,539

 
$
18,996

Work in-process
38,642

 
36,003

Finished goods
11,229

 
11,561

 
$
68,410

 
$
66,560


 
Property, plant and equipment, net:
 
September 30,
2014
 
June 30,
2014
 
(in thousands)
Land
$
4,950

 
$
4,950

Building
4,241

 
4,106

Manufacturing machinery and equipment
163,854

 
161,354

Equipment and tooling
10,644

 
10,486

Computer equipment and software
19,689

 
19,319

Office furniture and equipment
1,639

 
1,643

Leasehold improvements
25,386

 
25,154

 
230,403

 
227,012

Less: Accumulated depreciation
(121,543
)
 
(114,658
)
 
108,860

 
112,354

Equipment and construction in progress
12,039

 
10,900

Property, plant and equipment, net
$
120,899

 
$
123,254


Other long-term assets:
 
September 30,
2014
 
June 30,
2014
 
(in thousands)
Prepayments for property and equipment
$
1,782

 
$
1,435

Investment in a privately held company
100

 
100

Office leases deposits
401

 
428

 
$
2,283

 
$
1,963


Accrued liabilities:
 
September 30,
2014
 
June 30,
2014
 
(in thousands)
Accrued compensation and benefit
$
3,897

 
$
4,879

Accrued vacation
1,973

 
1,777

Accrued bonuses
1,947

 
1,873

Warranty accrual
1,230

 
1,346

Stock rotation accrual
1,607

 
1,645

Accrued professional fees
1,175

 
1,001

ESPP payable
810

 
323

Customer deposits
102

 
104

Accrued inventory
450

 
590

Accrued facilities related expenses
1,570

 
1,353

Other accrued expenses
2,516

 
2,485

 
$
17,277

 
$
17,376




The activities in the warranty accrual, included in accrued liabilities, are as follows:
 
Three Months Ended September 30,
 
2014
 
2013
 
(in thousands)
Beginning balance
$
1,346

 
$
1,428

Additions
530

 
285

Utilization
(646
)
 
(352
)
Ending balance
$
1,230

 
$
1,361


The activities in the stock rotation accrual, included in accrued liabilities, are as follows:
 
Three Months Ended September 30,
 
2014
 
2013
 
(in thousands)
Beginning balance
$
1,645

 
$
1,572

Additions
1,294

 
1,346

Utilization
(1,332
)
 
(1,321
)
Ending balance
$
1,607

 
$
1,597


Other Long-term liabilities:
 
September 30,
2014
 
June 30,
2014
 
(in thousands)
Deferred rent
$
1,096

 
$
1,143

Customer deposit
3

 
—

 
$
1,099

 
$
1,143

Debt
Debt
Debt
On May 11, 2012, the Company entered into a loan agreement with a financial institution that provides a term loan of $20.0 million for general purposes and a $10.0 million non-revolving credit line for the purchase of equipment. Both the term loan and equipment line will be fully repayable in May 2015. The borrowings may be made in the form of either Eurodollar loans or Base Rate loans. Eurodollar loans accrue interest based on an adjusted London Interbank Offered Rate ("LIBOR") as defined in the agreement, plus a margin of 1.00% to 1.75%. Base Rate loans accrue interest at the highest of (a) the lender's Prime Rate, (b) the Federal Funds Rate plus 0.5% and (c) the Eurodollar Rate (for a one-month interest period) plus 1%; plus a margin of -0.5% to 0.25%. The applicable margins for both Eurodollar loans and Base Rate loans will vary from time to time in the foregoing ranges based on the cash and cash equivalent balances maintained by the Company and its subsidiaries with the lender. In May 2013, the equipment credit line expired and there was no outstanding balance. As of September 30, 2014 and June 30, 2014, the outstanding balances of the term loan were $7.9 million and $13.6 million, respectively.

The obligations under the loan agreement are secured by substantially all assets of two subsidiaries of the Company, including, but not limited to, certain real property and related assets located at the Oregon fab. In addition, the Company and certain subsidiaries of the Company have agreed to guarantee full repayment and performance of the obligations under the loan agreement. The loan agreement contains customary restrictive covenants and includes certain financial covenants that require the Company to maintain on a consolidated basis specified financial ratios including total liabilities to tangible net worth, fixed charge coverage and current assets to current liabilities. As of September 30, 2014, the Company was in compliance with these covenants.
During July 2012, the Company entered into a loan agreement with the State of Oregon for an amount of $0.3 million. The loan was required to be used for training new and re-training existing employees of the Oregon fab. The loan bore a compound annual interest rate of 5.0% and was to be repaid in April 2014 if the required conditions were not met. In September 2014, the State of Oregon forgave the outstanding balance in full as we had satisfied the conditions. The $0.3 million loan forgiven was recorded as a reduction of costs of goods sold in our condensed consolidated statements of operations. There was no outstanding balance of the loan as of September 30, 2014.
Shareholders' Equity and Share-based Compensation
Shareholders' Equity and Share-based Compensation
Shareholders' Equity and Share-based Compensation
Share Repurchase
On October 22, 2010, the Company's Board of Directors authorized a $25.0 million share repurchase program. Under this repurchase program the Company may, from time to time, repurchase shares from the open market or in privately negotiated transactions, subject to supervision and oversight by the Board. The Company accounts for treasury stock under the cost method. Shares repurchased are accounted for as treasury shares and the total cost of shares repurchased is recorded as a reduction of shareholders' equity. From time to time, treasury shares may be reissued as part of the Company's stock-based compensation programs. Gains on re-issuance of treasury stock are credited to additional paid-in capital; losses are charged to additional paid-in capital to offset the net gains, if any, from previous sales or re-issuance of treasury stock. Any remaining balance of the losses are charged to retained earnings.
On May 8, 2014, the Company's Board of Directors approved to reactivate the share repurchase program with a remaining balance of $22.7 million. The Board authorized management to repurchase, subject to oversight by the Board, our common shares up to the remaining balance of the program, or $22.7 million. The repurchases may be made from the open market or through negotiated block transactions and to date repurchases have been made pursuant to a pre-established 10b5-1 trading plan. Such 10b5-1 trading plan was expired in August 2014 and the Board intends to review conditions from time to time to determine whether it is appropriate to implement a new 10b5-1 trading plan or to conduct repurchases under the program outside of a 10b5-1 trading plan.
During the three months ended September 30, 2014, the Company did not repurchased any shares under the program. As of September 30, 2014, the Company repurchased an aggregate of 361,364 shares for a total cost of $3.2 million, at an average repurchase price of $8.82 per share since inception of the program. No repurchased shares have been retired. Of the 361,364 repurchased shares, 21,650 shares with a weighted average repurchase price of $13.81 per share, were reissued at an average price of $3.00 per share for option exercises and vested RSU.

Stock Options
The following table summarizes the Company's stock option activities for the three months ended September 30, 2014:
 
 
 
Weighted
 
 
 
 
 
Average
 
 
 
Number of
 
Exercise Price
 
Aggregate
 
Shares
 
Per Share
 
Intrinsic Value
Outstanding at June 30, 2014
3,238,784

 
$
10.28

 
$
3,258,607

Granted
10,000

 
$
9.07

 
 
Exercised
(128,231
)
 
$
6.69

 
$
392,484

Canceled or forfeited
(17,484
)
 
$
15.87

 
 
Outstanding at September 30, 2014
3,103,069

 
$
10.40

 
$
3,118,240


Information with respect to stock options outstanding and exercisable at September 30, 2014 is as follows:
 
Options Outstanding  
 
Options Vested and Exercisable  
 
Number Outstanding
 
Weighted-Average
Remaining Contractual Life (years) 
 
Weighted-Average
Exercise Price
 
Number Exercisable
 
Weighted-Average
Exercise Price
Total options outstanding
3,103,069

 
5.68
 
$
10.40

 
2,115,149

 
$
11.26

Options vested and expected to vest
3,005,766

 
5.57
 
$
10.48

 
 
 
 
Options expected to vest are the result of applying the pre-vesting forfeiture rate assumption to total outstanding options.
The fair value of stock options granted were estimated at the date of grant using the Black-Scholes option valuation model for the three months ended September 30, 2014 with the following weighted average assumptions:
 
Three Months Ended September 30,
 
2014
Volatility rate
43.5%
Risk-free interest rate
1.7%
Expected term
5.5 years
Dividend yield
0%

Historically, the Company estimates its expected volatility based on that of the publicly traded shares of industry peers over a period equivalent to the expected term of the stock awards granted. Beginning in July 2015, the Company estimates its expected volatility based on a weighted average calculation of both the Company's volatility of its publicly traded share prices since its IPO and that of the publicly traded shares of industry peers over a period equivalent to the expected term of the stock awards granted.
Restricted Stock Units ("RSU")
The following table summarizes the Company's RSU activities for the three months ended September 30, 2014:
 
Number of Restricted Stock
Units
 
Weighted Average
Grant Date Fair
Value Per Share
 
Weighted Average
Remaining
Recognition
Period (Years)
 
Aggregate Intrinsic Value
Nonvested at June 30, 2014
656,374

 
$
8.40

 
1.77
 
$
6,084,587

Granted
25,500

 
$
9.48

 
 
 
 
Vested
(19,674
)
 
$
8.92

 
 
 
 
Forfeited
(29,950
)
 
$
8.41

 
 
 
 
Nonvested at September 30, 2014
632,250

 
$
8.43

 
1.61
 
$
5,943,150

RSUs vested and expected to vest
557,582

 
 
 
1.52
 
$
5,241,267

The fair value of RSU is estimated based on the market price of the Company's share on the date of grant.






Employee Share Purchase Plan
The Employee Share Purchase Plan (the "ESPP") was established in May 2010 upon the completion of the Company's initial public offering. The assumptions used to estimate the fair values of common shares issued under the ESPP were as follows:
 
 
 
Three Months Ended September 30,
 
2014
Volatility rate
50%
Risk-free interest rate
0.1% - 0.4%
Expected term
1.3 years
Dividend yield
0%

Share-based Compensation Expense
The total share-based compensation expense related to stock options, ESPP and RSUs described above, recognized in the condensed consolidated statements of operations for the periods presented was as follows:
 
Three Months Ended September 30,
 
2014
 
2013
 
(in thousands)
Cost of goods sold
$
154

 
$
196

Research and development
206

 
295

Selling, general and administrative
742

 
718

 
$
1,102

 
$
1,209


Total unrecognized stock-based compensation expense as of September 30, 2014 was $4.7 million, which includes estimated forfeitures and is expected to be recognized over a weighted-average period of 1.4 years.
Income Taxes
Income Taxes
Income Taxes
The Company recognized income tax expense of approximately $1.2 million and $1.0 million for the three months ended September 30, 2014 and 2013, respectively. The estimated effective tax rate for the three months ended September 30, 2014 was 67.5% compared to 76.5% for the three months ended September 30, 2013. The effective tax rate for the three months ended September 30, 2014 was lower than the effective tax rate for the same period last year primarily due to the changes in the mix of earnings in various geographic jurisdictions between the two periods.
The Company files its income tax returns in the United States and in various foreign jurisdictions. The tax years 2001 to 2014 remain open to examination by U.S. federal and state tax authorities. The tax years 2005 to 2014 remain open to examination by foreign tax authorities.
The Company's income tax returns are subject to examinations by the Internal Revenue Service and other tax authorities in various jurisdictions. In accordance with the guidance on the accounting for uncertainty in income taxes, the Company regularly assesses the likelihood of adverse outcomes resulting from these examinations to determine the adequacy of its provision for income taxes. These assessments can require considerable estimates and judgments. As of September 30, 2014, the gross amount of unrecognized tax benefits was approximately $6.8 million, of which $4.8 million that, if recognized, would reduce the effective income tax rate in future periods. If the Company's estimate of income tax liabilities proves to be less than the ultimate assessment, then a further charge to expense would be required. If events occur and the payment of these amounts ultimately proves to be unnecessary, the reversal of the liabilities would result in tax benefits being recognized in the period when the Company determines the liabilities are no longer necessary. The Company does not anticipate any material changes to its uncertain tax positions during the next twelve months.
Segment and Geographic Information
Segment and Geographic Information
Segment and Geographic Information
The Company is organized as, and operates in, one operating segment: the design, development and supply of power semiconductor products for computing, consumer electronics, communication and industrial applications. The chief operating decision-maker is the Chief Executive Officer. The financial information presented to the Company's Chief Executive Officer is on a consolidated basis, accompanied by information about revenue by customer and geographic region, for purposes of evaluating financial performance and allocating resources. The Company has one business segment, and there are no segment managers who are held accountable for operations, operating results and plans for products or components below the consolidated unit level. Accordingly, the Company reports as a single operating segment.
The Company sells its products primarily to distributors in the Asia Pacific region, who in turn sell these products to end customers. Because the Company's distributors sell their products to end customers which may have a global presence, revenue by geographical location is not necessarily representative of the geographical distribution of sales to end user markets.
The revenue by geographical location in the following tables is based on the country or region to which the products were shipped to:
 
Three Months Ended September 30,
 
2014
 
2013
 
(in thousands)
Hong Kong
$
75,247

 
$
71,256

China
10,957

 
10,892

South Korea
639

 
797

United States
683

 
473

Other countries
691

 
703

 
$
88,217

 
$
84,121

The following is a summary of revenue by product type:
 
Three Months Ended September 30,
 
2014
 
2013
 
(in thousands)
Power discrete
$
64,891

 
$
65,145

Power IC
19,156

 
13,612

Packaging and testing services
4,170

 
5,364

 
$
88,217

 
$
84,121

 
Long-lived assets, net consisting of property, plant and equipment, by geographical area are as follows:
 
September 30,
2014
 
June 30,
2014
 
(in thousands)
China
$
79,262

 
$
80,736

United States
41,245

 
42,106

Other Countries
392

 
412

 
$
120,899

 
$
123,254

Commitments and Contingencies
Commitments and Contingencies
Commitments and Contingencies
Purchase Commitments
As of September 30, 2014 and June 30, 2014, the Company had approximately $20.6 million and $34.5 million, respectively, of outstanding purchase commitments primarily for purchases of semiconductor raw materials, wafers, spare parts and packaging and testing services, and approximately $2.5 million and $4.6 million, respectively, of capital commitments for the purchase of property and equipment.
Contingencies and Indemnities
The Company is currently not a party to any pending material legal proceedings. The Company has in the past, and may from time to time in the future, become involved in legal proceedings arising from the normal course of business activities.  The semiconductor industry is characterized by frequent claims and litigation, including claims regarding patent and other intellectual property rights as well as improper hiring practices. Irrespective of the validity of such claims, the Company could incur significant costs in the defense of such claims and suffer adverse effects on its operations.
The Company is a party to a variety of agreements that it has contracted with various third parties. Pursuant to these agreements, the Company may be obligated to indemnify another party to such an agreement with respect to certain matters. Typically, these obligations arise in the context of contracts entered into by the Company, under which the Company customarily agrees to hold the other party harmless against losses arising from a breach of representations and covenants related to such matters as title to assets sold, certain intellectual property rights, specified environmental matters and certain income taxes. In these circumstances, payment by the Company is customarily conditioned on the other party making a claim pursuant to the procedures specified in the particular contract, which procedures typically allow the Company to challenge the other party's claim. Further, the Company's obligations under these agreements may be limited in time and/or amount, and in some instances, the Company may have recourse against third parties for certain payments made by it under these agreements. The Company has not historically paid or recorded any material indemnifications and no accrual has been made at September 30, 2014 and June 30, 2014.
The Company has agreed to indemnify its directors and certain employees as permitted by law and pursuant to its bye-laws, and has entered into indemnification agreements with its directors and executive officers. The Company has not recorded a liability associated with these indemnification arrangements, as it historically has not incurred any material costs associated with such indemnification obligations. Costs associated with such indemnification obligations may be mitigated by insurance coverage that the Company maintains. However, such insurance may not cover any, or may cover only a portion of, the amounts the Company may be required to pay. In addition, the Company may not be able to maintain such insurance coverage in the future.
The Company and Significant Accounting Policies (Policies)
Concentration Risk, Credit Risk, Policy [Policy Text Block] 
The Company manages its credit risk associated with exposure to distributors and direct customers on outstanding accounts receivable through the application of credit approvals, credit ratings and other monitoring procedures. In some instances, the Company also obtains letters of credit from certain customers.
Credit sales, which are mainly on credit terms of 30 to 60 days, are only made to customers who meet the Company's credit requirements, while sales to new customers or customers with low credit ratings are usually made on an advance payment basis. The Company considers its trade accounts receivable to be of good credit quality because its key distributors and direct customers have long-standing business relationships with the Company and the Company has not experienced any significant bad debt write-offs of accounts receivable in the past. The Company closely monitors the aging of accounts receivable from its distributors and direct customers, and regularly reviews their financial positions, when available.
Basis of Preparation 
Basis of Preparation
The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) for interim financial information and with the instructions to Article 10 of Securities and Exchange Commission Regulation S-X, as amended. They do not include all information and footnotes necessary for a fair presentation of financial position, results of operations and cash flows in conformity with U.S. GAAP for complete financial statements. These condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and related notes contained in the Company’s Annual Report on Form 10-K for the fiscal year ended June 30, 2014. All significant intercompany balances and transactions have been eliminated in consolidation. In the opinion of management, all adjustments (consisting of normal recurring adjustments and accruals) considered necessary for a fair presentation of the results of operations for the period presented have been included in the interim periods. Operating results for the three months ended September 30, 2014 are not necessarily indicative of the results that may be expected for the fiscal year ending June 30, 2015. The condensed consolidated balance sheet at June 30, 2014 is derived from the audited financial statements included in the Company’s Annual Report on Form 10-K for the fiscal year ended June 30, 2014.
Use of Estimates 
Use of Estimates
The preparation of the condensed consolidated financial statements in conformity with U.S. GAAP requires the Company to make estimates, judgments and assumptions that affect the reported amounts of assets, liabilities, revenue and expenses. To the extent there are material differences between these estimates and actual results, the Company's condensed consolidated financial statements will be affected. On an ongoing basis, the Company evaluates the estimates, judgments and assumptions including those related to stock rotation returns, price adjustments, allowance for doubtful accounts, inventory reserves, warranty accrual, income taxes, share-based compensation, and useful lives for property, plant and equipment and intangible assets.
Fair Value of Financial Instruments 
Fair Value of Financial Instruments
The fair value of cash equivalents are based on observable market prices and have been categorized in Level 1 in the fair value hierarchy. Cash equivalents consist primarily of short term bank deposits. The carrying values of financial instruments such as cash and cash equivalents, accounts receivable and accounts payable approximate their carrying values due to their short-term maturities. The carrying value of the Company's debt is considered a reasonable estimate of fair value which is estimated by considering the current rates available to the Company for debt of the same remaining maturities, structure and terms of the debts.
Comprehensive Income (Loss) 
Comprehensive Income (Loss)
Comprehensive income (loss) is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources. The Company's accumulated other comprehensive income (loss) consists of cumulative foreign currency translation adjustments. Total comprehensive income (loss) is presented in the condensed consolidated statements of comprehensive income (loss).
Recent Accounting Pronouncements 
Recent Accounting Pronouncements
    
In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (“ASU 2014-09”). The standard provides companies with a single model for use in accounting for revenue arising from contracts with customers and supersedes current revenue recognition guidance, including industry-specific revenue guidance. The core principle of the model is to recognize revenue when control of the goods or services transfers to the customer, as opposed to recognizing revenue when the risks and rewards transfer to the customer under the existing revenue guidance. ASU 2014-09 is effective for annual reporting periods beginning after December 15, 2016. Early adoption is not permitted. The guidance permits companies to either apply the requirements retrospectively to all prior periods presented, or apply the requirements in the year of adoption, through a cumulative adjustment. The Company is in the process of evaluating the impact of adoption on its consolidated financial statements.
Net Income Per Share (Tables)
Schedule of Earnings Per Share, Basic and Diluted 
The following table presents the calculation of basic and diluted net income per share:
 
Three Months Ended September 30,
 
2014
 
2013
 
(in thousands, except per share data)
Numerator:
 
 
 
Net income
$
564

 
$
307

 
 
 
 
Denominator:
 
 
 
Basic:
 
 
 
Weighted average number of common shares used to compute basic net income per share
26,385

 
25,684

Diluted:
 
 
 
Weighted average number of common shares used to compute basic net income per share
26,385

 
25,684

Effect of potentially dilutive securities:
 
 
 
Stock options, RSUs and ESPP shares
618

 
625

Weighted average number of common shares used to compute diluted net income per share
27,003

 
26,309

Net income per share:
 
 
 
Basic
$
0.02

 
$
0.01

Diluted
$
0.02

 
$
0.01

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share 
The following potential dilutive securities were excluded from the computation of diluted net income per share as their effect would have been anti-dilutive:
 
Three Months Ended September 30,
 
2014
 
2013
 
(in thousands)
Employee stock options and RSUs
2,393

 
2,783

ESPP to purchase common shares
—

 
307

Total potential dilutive securities
2,393

 
3,090

Concentration of Credit Risk and Significant Customers (Tables)
Schedules of Concentration of Risk, by Risk Factor
Summarized below are individual customers whose revenue or accounts receivable balances were 10% or higher than the respective total consolidated amounts:
 
Three Months Ended September 30,
Percentage of revenue
2014
 
2013
Customer A
24.1
%
 
20.6
%
Customer B
39.6
%
 
44.3
%
Customer C
12.9
%
 
11.8
%

 
September 30,
2014
 
June 30,
2014
Percentage of accounts receivable
 
Customer A
32.6
%
 
23.1
%
Customer B
15.6
%
 
30.5
%
Customer C
24.7
%
 
17.4
%
Balance Sheet Components (Tables)
Schedule of Accounts, Notes, Loans and Financing Receivable 
Accounts receivable:
 
September 30,
2014
 
June 30,
2014
 
(in thousands)
Accounts receivable
$
50,657

 
$
51,128

Less: Allowance for price adjustments
(15,561
)
 
(14,563
)
Less: Allowance for doubtful accounts
(30
)
 
(30
)
Accounts receivable, net
$
35,066

 
$
36,535

Schedule of Inventory, Current 
Inventories:
 
September 30,
2014
 
June 30,
2014
 
(in thousands)
Raw materials
$
18,539

 
$
18,996

Work in-process
38,642

 
36,003

Finished goods
11,229

 
11,561

 
$
68,410

 
$
66,560

Property, Plant and Equipment 
Property, plant and equipment, net:
 
September 30,
2014
 
June 30,
2014
 
(in thousands)
Land
$
4,950

 
$
4,950

Building
4,241

 
4,106

Manufacturing machinery and equipment
163,854

 
161,354

Equipment and tooling
10,644

 
10,486

Computer equipment and software
19,689

 
19,319

Office furniture and equipment
1,639

 
1,643

Leasehold improvements
25,386

 
25,154

 
230,403

 
227,012

Less: Accumulated depreciation
(121,543
)
 
(114,658
)
 
108,860

 
112,354

Equipment and construction in progress
12,039

 
10,900

Property, plant and equipment, net
$
120,899

 
$
123,254

Schedule of Other Assets, Noncurrent 
Other long-term assets:
 
September 30,
2014
 
June 30,
2014
 
(in thousands)
Prepayments for property and equipment
$
1,782

 
$
1,435

Investment in a privately held company
100

 
100

Office leases deposits
401

 
428

 
$
2,283

 
$
1,963

Schedule of Accrued Liabilities 
Accrued liabilities:
 
September 30,
2014
 
June 30,
2014
 
(in thousands)
Accrued compensation and benefit
$
3,897

 
$
4,879

Accrued vacation
1,973

 
1,777

Accrued bonuses
1,947

 
1,873

Warranty accrual
1,230

 
1,346

Stock rotation accrual
1,607

 
1,645

Accrued professional fees
1,175

 
1,001

ESPP payable
810

 
323

Customer deposits
102

 
104

Accrued inventory
450

 
590

Accrued facilities related expenses
1,570

 
1,353

Other accrued expenses
2,516

 
2,485

 
$
17,277

 
$
17,376

Schedule of Product Warranty Liability 
The activities in the warranty accrual, included in accrued liabilities, are as follows:
 
Three Months Ended September 30,
 
2014
 
2013
 
(in thousands)
Beginning balance
$
1,346

 
$
1,428

Additions
530

 
285

Utilization
(646
)
 
(352
)
Ending balance
$
1,230

 
$
1,361

Stock Rotation Accrual 
The activities in the stock rotation accrual, included in accrued liabilities, are as follows:
 
Three Months Ended September 30,
 
2014
 
2013
 
(in thousands)
Beginning balance
$
1,645

 
$
1,572

Additions
1,294

 
1,346

Utilization
(1,332
)
 
(1,321
)
Ending balance
$
1,607

 
$
1,597

Schedule of Other Noncurrent Liabilities 
Other Long-term liabilities:
 
September 30,
2014
 
June 30,
2014
 
(in thousands)
Deferred rent
$
1,096

 
$
1,143

Customer deposit
3

 
—

 
$
1,099

 
$
1,143

Shareholders' Equity and Share-based Compensation (Tables)
Summary of Stock Option Activities 
Stock Options
The following table summarizes the Company's stock option activities for the three months ended September 30, 2014:
 
 
 
Weighted
 
 
 
 
 
Average
 
 
 
Number of
 
Exercise Price
 
Aggregate
 
Shares
 
Per Share
 
Intrinsic Value
Outstanding at June 30, 2014
3,238,784

 
$
10.28

 
$
3,258,607

Granted
10,000

 
$
9.07

 
 
Exercised
(128,231
)
 
$
6.69

 
$
392,484

Canceled or forfeited
(17,484
)
 
$
15.87

 
 
Outstanding at September 30, 2014
3,103,069

 
$
10.40

 
$
3,118,240


Information with respect to stock options outstanding and exercisable at September 30, 2014 is as follows:
 
Options Outstanding  
 
Options Vested and Exercisable  
 
Number Outstanding
 
Weighted-Average
Remaining Contractual Life (years) 
 
Weighted-Average
Exercise Price
 
Number Exercisable
 
Weighted-Average
Exercise Price
Total options outstanding
3,103,069

 
5.68
 
$
10.40

 
2,115,149

 
$
11.26

Options vested and expected to vest
3,005,766

 
5.57
 
$
10.48

 
 
 
 
Options expected to vest are the result of applying the pre-vesting forfeiture rate assumption to total outstanding options.
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] 
The fair value of stock options granted were estimated at the date of grant using the Black-Scholes option valuation model for the three months ended September 30, 2014 with the following weighted average assumptions:
 
Three Months Ended September 30,
 
2014
Volatility rate
43.5%
Risk-free interest rate
1.7%
Expected term
5.5 years
Dividend yield
0%
Restricted Stock Units Activity 
Restricted Stock Units ("RSU")
The following table summarizes the Company's RSU activities for the three months ended September 30, 2014:
 
Number of Restricted Stock
Units
 
Weighted Average
Grant Date Fair
Value Per Share
 
Weighted Average
Remaining
Recognition
Period (Years)
 
Aggregate Intrinsic Value
Nonvested at June 30, 2014
656,374

 
$
8.40

 
1.77
 
$
6,084,587

Granted
25,500

 
$
9.48

 
 
 
 
Vested
(19,674
)
 
$
8.92

 
 
 
 
Forfeited
(29,950
)
 
$
8.41

 
 
 
 
Nonvested at September 30, 2014
632,250

 
$
8.43

 
1.61
 
$
5,943,150

RSUs vested and expected to vest
557,582

 
 
 
1.52
 
$
5,241,267

The fair value of RSU is estimated based on the market price of the Company's share on the date of grant.
Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block] 
Employee Share Purchase Plan
The Employee Share Purchase Plan (the "ESPP") was established in May 2010 upon the completion of the Company's initial public offering. The assumptions used to estimate the fair values of common shares issued under the ESPP were as follows:
 
 
 
Three Months Ended September 30,
 
2014
Volatility rate
50%
Risk-free interest rate
0.1% - 0.4%
Expected term
1.3 years
Dividend yield
0%
Share-based Compensation, Allocation of Recognized Period Costs 
Share-based Compensation Expense
The total share-based compensation expense related to stock options, ESPP and RSUs described above, recognized in the condensed consolidated statements of operations for the periods presented was as follows:
 
Three Months Ended September 30,
 
2014
 
2013
 
(in thousands)
Cost of goods sold
$
154

 
$
196

Research and development
206

 
295

Selling, general and administrative
742

 
718

 
$
1,102

 
$
1,209

Segment and Geographic Information (Tables)
Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas 
Long-lived assets, net consisting of property, plant and equipment, by geographical area are as follows:
 
September 30,
2014
 
June 30,
2014
 
(in thousands)
China
$
79,262

 
$
80,736

United States
41,245

 
42,106

Other Countries
392

 
412

 
$
120,899

 
$
123,254

The revenue by geographical location in the following tables is based on the country or region to which the products were shipped to:
 
Three Months Ended September 30,
 
2014
 
2013
 
(in thousands)
Hong Kong
$
75,247

 
$
71,256

China
10,957

 
10,892

South Korea
639

 
797

United States
683

 
473

Other countries
691

 
703

 
$
88,217

 
$
84,121

Revenue from External Customers by Products and Services 
The following is a summary of revenue by product type:
 
Three Months Ended September 30,
 
2014
 
2013
 
(in thousands)
Power discrete
$
64,891

 
$
65,145

Power IC
19,156

 
13,612

Packaging and testing services
4,170

 
5,364

 
$
88,217

 
$
84,121

Net Income Per Share - Basic and Diluted Income Per Share (Details) (USD $)
In Thousands, except Per Share data, unless otherwise specified
3 Months Ended
Sep. 30, 2014
Sep. 30, 2013
Numerator:
 
 
Net income
$ 564 
$ 307 
Basic:
 
 
Weighted average number of common shares used to compute basic net income per share
26,385 
25,684 
Effect of potentially dilutive securities:
 
 
Stock options, RSUs and ESPP shares (in shares)
618 
625 
Weighted average number of common shares used to compute diluted net income per share
27,003 
26,309 
Net income per share:
 
 
Basic (in dollars per share)
$ 0.02 
$ 0.01 
Diluted (in dollars per share)
$ 0.02 
$ 0.01 
Net Income Per Share - Potential Dilutive Shares (Details)
In Thousands, unless otherwise specified
3 Months Ended
Sep. 30, 2014
Sep. 30, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
 
 
Potential dilutive securities (in shares)
2,393 
3,090 
Employee stock options and RSUs
 
 
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
 
 
Potential dilutive securities (in shares)
2,393 
2,783 
ESPP to purchase common shares
 
 
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
 
 
Potential dilutive securities (in shares)
0 
307 
Concentration of Credit Risk and Significant Customers - (Details)
3 Months Ended
Sep. 30, 2014
Minimum
Sep. 30, 2014
Maximum
Sep. 30, 2014
Customer A
Sales Revenue, Goods, Net
Customer Concentration Risk
Sep. 30, 2013
Customer A
Sales Revenue, Goods, Net
Customer Concentration Risk
Sep. 30, 2014
Customer A
Accounts Receivable
Customer Concentration Risk
Jun. 30, 2014
Customer A
Accounts Receivable
Customer Concentration Risk
Sep. 30, 2014
Customer B
Sales Revenue, Goods, Net
Customer Concentration Risk
Sep. 30, 2013
Customer B
Sales Revenue, Goods, Net
Customer Concentration Risk
Sep. 30, 2014
Customer B
Accounts Receivable
Customer Concentration Risk
Jun. 30, 2014
Customer B
Accounts Receivable
Customer Concentration Risk
Sep. 30, 2014
Customer C
Sales Revenue, Goods, Net
Customer Concentration Risk
Sep. 30, 2013
Customer C
Sales Revenue, Goods, Net
Customer Concentration Risk
Sep. 30, 2014
Customer C
Accounts Receivable
Customer Concentration Risk
Jun. 30, 2014
Customer C
Accounts Receivable
Customer Concentration Risk
Concentration Risk
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Terms of credit sales, (in days)
30 days 
60 days 
 
 
 
 
 
 
 
 
 
 
 
 
Customers greater than 10% of total
 
 
24.10% 
20.60% 
32.60% 
23.10% 
39.60% 
44.30% 
15.60% 
30.50% 
12.90% 
11.80% 
24.70% 
17.40% 
Balance Sheet Components - Accounts receivable (Details) (USD $)
In Thousands, unless otherwise specified
Sep. 30, 2014
Jun. 30, 2014
Balance Sheet Related Disclosures [Abstract]
 
 
Accounts receivable
$ 50,657 
$ 51,128 
Less: allowance for price adjustments
(15,561)
(14,563)
Less: allowance for doubtful accounts
(30)
(30)
Accounts receivable, net
$ 35,066 
$ 36,535 
Balance Sheet Components - Inventories (Details) (USD $)
In Thousands, unless otherwise specified
Sep. 30, 2014
Jun. 30, 2014
Balance Sheet Related Disclosures [Abstract]
 
 
Raw materials
$ 18,539 
$ 18,996 
Work in-process
38,642 
36,003 
Finished goods
11,229 
11,561 
Inventory, net
$ 68,410 
$ 66,560 
Balance Sheet Components - Property, plant, and equipment (Details) (USD $)
In Thousands, unless otherwise specified
Sep. 30, 2014
Jun. 30, 2014
Property, Plant and Equipment [Line Items]
 
 
Property, plant, and equipment excluding equipment and construction In progress, gross
$ 230,403 
$ 227,012 
Less accumulated depreciation
(121,543)
(114,658)
Property, plant and equipment excluding equipment and construction in progress, net
108,860 
112,354 
Equipment and construction in progress
12,039 
10,900 
Property, plant and equipment, net
120,899 
123,254 
Land
 
 
Property, Plant and Equipment [Line Items]
 
 
Property, plant, and equipment excluding equipment and construction In progress, gross
4,950 
4,950 
Building
 
 
Property, Plant and Equipment [Line Items]
 
 
Property, plant, and equipment excluding equipment and construction In progress, gross
4,241 
4,106 
Manufacturing machinery and equipment
 
 
Property, Plant and Equipment [Line Items]
 
 
Property, plant, and equipment excluding equipment and construction In progress, gross
163,854 
161,354 
Equipment and tooling
 
 
Property, Plant and Equipment [Line Items]
 
 
Property, plant, and equipment excluding equipment and construction In progress, gross
10,644 
10,486 
Computer equipment and software
 
 
Property, Plant and Equipment [Line Items]
 
 
Property, plant, and equipment excluding equipment and construction In progress, gross
19,689 
19,319 
Office furniture and equipment
 
 
Property, Plant and Equipment [Line Items]
 
 
Property, plant, and equipment excluding equipment and construction In progress, gross
1,639 
1,643 
Leasehold improvements
 
 
Property, Plant and Equipment [Line Items]
 
 
Property, plant, and equipment excluding equipment and construction In progress, gross
$ 25,386 
$ 25,154 
Balance Sheet Components - Other long term assets (Details) (USD $)
In Thousands, unless otherwise specified
Sep. 30, 2014
Jun. 30, 2014
Balance Sheet Related Disclosures [Abstract]
 
 
Prepayments for property and equipment
$ 1,782 
$ 1,435 
Investment in a privately held company
100 
100 
Office leases deposits
401 
428 
Other long-term assets
$ 2,283 
$ 1,963 
Balance Sheet Components - Accrued liabilities (Details) (USD $)
In Thousands, unless otherwise specified
Sep. 30, 2014
Jun. 30, 2014
Sep. 30, 2013
Jun. 30, 2013
Balance Sheet Related Disclosures [Abstract]
 
 
 
 
Accrued compensation and benefit
$ 3,897 
$ 4,879 
 
 
Accrued vacation
1,973 
1,777 
 
 
Accrued bonuses
1,947 
1,873 
 
 
Warranty accrual
1,230 
1,346 
1,361 
1,428 
Stock rotation accrual
1,607 
1,645 
1,597 
1,572 
Accrued professional fees
1,175 
1,001 
 
 
ESPP payable
810 
323 
 
 
Customer deposits
102 
104 
 
 
Accrued inventory
450 
590 
 
 
Accrued facilities related expenses
1,570 
1,353 
 
 
Other accrued expenses
2,516 
2,485 
 
 
Accrued liabilities
$ 17,277 
$ 17,376 
 
 
Balance Sheet Components - Product Warranty Accrual (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended
Sep. 30, 2014
Sep. 30, 2013
Movement in Standard and Extended Product Warranty, Increase (Decrease) [Roll Forward]
 
 
Beginning balance
$ 1,346 
$ 1,428 
Additions
530 
285 
Utilization
(646)
(352)
Ending balance
$ 1,230 
$ 1,361 
Balance Sheet Components - Stock Rotation Accrual (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended
Sep. 30, 2014
Sep. 30, 2013
Stock Rotation Accrual Increae (Decrease) [Roll Forward]
 
 
Beginning balance
$ 1,645 
$ 1,572 
Additions
1,294 
1,346 
Utilization
(1,332)
(1,321)
Ending balance
$ 1,607 
$ 1,597 
Balance Sheet Components - Other Long Term Liability (Details) (USD $)
In Thousands, unless otherwise specified
Sep. 30, 2014
Jun. 30, 2014
Balance Sheet Related Disclosures [Abstract]
 
 
Deferred rent
$ 1,096 
$ 1,143 
Customer deposit
3 
0 
Other long term liabilities
$ 1,099 
$ 1,143 
Debt - (Details) (USD $)
3 Months Ended 0 Months Ended
Sep. 30, 2014
Sep. 30, 2013
Sep. 30, 2014
Variable Interest Rate Term Loan Maturing May 2015
Notes Payable to Banks
subsidiary
Jun. 30, 2014
Variable Interest Rate Term Loan Maturing May 2015
Notes Payable to Banks
May 11, 2012
Variable Interest Rate Term Loan Maturing May 2015
Notes Payable to Banks
Sep. 30, 2014
State of Oregon Loan
Loans Payable
Jul. 17, 2012
State of Oregon Loan
Loans Payable
May 11, 2012
London Interbank Offered Rate (LIBOR) [Member]
Minimum
May 11, 2012
London Interbank Offered Rate (LIBOR) [Member]
Maximum
May 11, 2012
Federal Funds Rate [Member]
May 11, 2012
Eurodollar [Member]
May 11, 2012
Eurodollar [Member]
Minimum
May 11, 2012
Eurodollar [Member]
Maximum
Debt Instrument [Line Items]
 
 
 
 
 
 
 
 
 
 
 
 
 
Line of Credit Facility, Amount Outstanding
 
 
$ 0 
 
 
 
 
 
 
 
 
 
 
Loan, principal amount
 
 
 
 
20,000,000.0 
 
250,000 
 
 
 
 
 
 
Line of Credit Facility, Maximum Borrowing Capacity
 
 
 
 
10,000,000.0 
 
 
 
 
 
 
 
 
Debt instrument, basis spread on variable rate
 
 
 
 
 
 
 
1.00% 
1.75% 
0.50% 
1.00% 
(0.50%)
0.25% 
Outstanding balance of loan
 
 
7,900,000 
13,600,000 
 
0 
 
 
 
 
 
 
 
Number of subsidiaries securing obligations under loan agreement
 
 
2 
 
 
 
 
 
 
 
 
 
 
Interest rate on loan
 
 
 
 
 
 
5.00% 
 
 
 
 
 
 
Forgiveness of loan
$ (250,000)
$ 0 
 
 
 
 
 
 
 
 
 
 
 
Shareholders' Equity and Share-based Compensation - Shares Repurchase (Details) (USD $)
0 Months Ended 3 Months Ended 47 Months Ended
May 8, 2014
Oct. 22, 2010
Sep. 30, 2014
Sep. 30, 2014
Class of Stock [Line Items]
 
 
 
 
Share repurchase program, authorized amount (USD in Millions)
 
$ 25,000,000 
 
 
Shares Repurchase Program Remaining Balance
22,700,000 
 
 
 
Treasury stock acquired, shares repurchased (in shares)
 
 
0 
361,364 
Treasury Stock, Value, Acquired, Cost Method
 
 
 
$ 3,200,000 
Treasury stock acquired, average price per share (in dollars per share)
 
 
 
$ 8.82 
Treasury Stock, Shares, Retired
 
 
 
0 
Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures (in shares)
 
 
 
21,650 
Treasury Stock Reissued, Average Price Per Share
 
 
 
$ 3.00 
Treasury Stock Reissued
 
 
 
 
Class of Stock [Line Items]
 
 
 
 
Treasury stock acquired, average price per share (in dollars per share)
 
 
 
$ 13.81 
Shareholders' Equity and Share-based Compensation - Share-based Compensation (Details) (USD $)
3 Months Ended 47 Months Ended
Sep. 30, 2014
Sep. 30, 2014
Jun. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
 
 
 
Treasury stock acquired, shares repurchased (in shares)
0 
361,364 
 
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
 
 
 
Outstanding at June 30, 2014 (in shares)
3,238,784 
 
 
Granted (in shares)
10,000 
 
 
Exercised (in shares)
(128,231)
 
 
Canceled or forfeited (in shares)
(17,484)
 
 
Outstanding at September 30, 2014 (in shares)
3,103,069 
3,103,069 
 
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
 
 
 
Outstanding at June 30, 2014 (in dollars per share)
$ 10.28 
 
 
Granted (in dollars per share)
$ 9.07 
 
 
Exercised (in dollars per share)
$ 6.69 
 
 
Canceled or forfeited (in dollars per share)
$ 15.87 
 
 
Outstanding at September 30, 2014 (in dollars per share)
$ 10.40 
$ 10.40 
 
Options Outstanding Aggregate Intrinsic Value
$ 3,118,240 
$ 3,118,240 
$ 3,258,607 
Options Exercised Aggregate Intrinsic Value
$ 392,484 
 
 
Employee Stock [Member]
 
 
 
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
 
 
 
Volatility Rate
50.00% 
 
 
Expected Term
1 year 3 months 18 days 
 
 
Expected Dividend Rate
0.00% 
 
 
Employee Stock [Member] |
Minimum
 
 
 
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
 
 
 
Risk Free Interest Rate
0.10% 
 
 
Employee Stock [Member] |
Maximum
 
 
 
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
 
 
 
Risk Free Interest Rate
0.40% 
 
 
Stock Options [Member]
 
 
 
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
 
 
 
Volatility Rate
43.50% 
 
 
Risk Free Interest Rate
1.70% 
 
 
Expected Term
5 years 6 months 
 
 
Expected Dividend Rate
0.00% 
 
 
Shareholders' Equity and Share-based Compensation - Stock Options Outstanding and Exercisable (Details) (USD $)
3 Months Ended
Sep. 30, 2014
Jun. 30, 2014
Share-based Compensation [Abstract]
 
 
Options, Number Outstanding (in shares)
3,103,069 
3,238,784 
Options, Weighted-Average Remaining Contractual Life (in years)
5 years 8 months 5 days 
 
Options, Weighted-Average Exercise Price (in dollars per share)
$ 10.40 
$ 10.28 
Options, Number Exercisable (in shares)
2,115,149 
 
Options, Weighted-Average Exercise Price (in dollars per share)
$ 11.26 
 
Options vested and expected to vest, Number Outstanding (in shares)
3,005,766 
 
Options vested and expected to vest, Weighted Average Remaining Contractual Life (in years)
5 years 6 months 26 days 
 
Options vested and expected to vest, Weighted Average Exercise Price (in dollars per share)
$ 10.48 
 
Shareholders' Equity and Share-based Compensation - Restricted Stock Activity (Details) (USD $)
3 Months Ended
Sep. 30, 2014
Jun. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
 
 
Weighted Average Remaining Recognition Period (Years)
1 year 4 months 24 days 
 
Restricted Stock
 
 
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
 
 
Nonvested
656,374 
 
Granted
25,500 
 
Vested
(19,674)
 
Forfeited
(29,950)
 
Nonvested
632,250 
656,374 
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
 
 
Nonvested
$ 8.40 
 
Granted
$ 9.48 
 
Vested
$ 8.92 
 
Forfeited
$ 8.41 
 
Nonvested
$ 8.43 
$ 8.40 
Weighted Average Remaining Recognition Period (Years)
1 year 7 months 10 days 
1 year 9 months 7 days 
RSUs Nonvested Aggregate Intrinsic Value
$ 5,943,150 
$ 6,084,587 
RSUs vested and expected to vest, Outstanding (in shares)
557,582 
 
RSUs vested and expected to vest, Weighted Average Remaining Recognition Period (in years)
1 year 6 months 7 days 
 
RSUs vested and expected to vest, Aggregate Intrinsic Value
$ 5,241,267 
 
Shareholders' Equity and Share-based Compensation - Share-based Compensation Expenses (Details) (USD $)
3 Months Ended
Sep. 30, 2014
Sep. 30, 2013
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
 
 
Allocated share-based compensation expense
$ 1,102,000 
$ 1,209,000 
Unrecognized compensation expense
4,700,000 
 
Recognition period of share-based compensation expense (in years)
1 year 4 months 24 days 
 
Cost of goods sold
 
 
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
 
 
Allocated share-based compensation expense
154,000 
196,000 
Research and development
 
 
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
 
 
Allocated share-based compensation expense
206,000 
295,000 
Selling, general and administrative
 
 
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
 
 
Allocated share-based compensation expense
$ 742,000 
$ 718,000 
Income Taxes - Narrative (Details) (USD $)
3 Months Ended
Sep. 30, 2014
Sep. 30, 2013
Income Tax Disclosure [Abstract]
 
 
Income tax expense
$ 1,171,000 
$ 1,002,000 
Estimated effective income tax rate
67.50% 
76.50% 
Unrecognized tax benefits
6,800,000 
 
Unrecognized Tax Benefit, Amount Netted Against Deferred Tax Assets
$ 4,800,000 
 
Segment and Geographic Information - Revenue by Location and Product Type (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended
Sep. 30, 2014
Sep. 30, 2013
Revenues from External Customers and Long-Lived Assets [Line Items]
 
 
Revenue
$ 88,217 
$ 84,121 
Power discrete
 
 
Revenues from External Customers and Long-Lived Assets [Line Items]
 
 
Revenue
64,891 
65,145 
Power IC
 
 
Revenues from External Customers and Long-Lived Assets [Line Items]
 
 
Revenue
19,156 
13,612 
Packaging and testing services
 
 
Revenues from External Customers and Long-Lived Assets [Line Items]
 
 
Revenue
4,170 
5,364 
Hong Kong
 
 
Revenues from External Customers and Long-Lived Assets [Line Items]
 
 
Revenue
75,247 
71,256 
China
 
 
Revenues from External Customers and Long-Lived Assets [Line Items]
 
 
Revenue
10,957 
10,892 
South Korea
 
 
Revenues from External Customers and Long-Lived Assets [Line Items]
 
 
Revenue
639 
797 
United States
 
 
Revenues from External Customers and Long-Lived Assets [Line Items]
 
 
Revenue
683 
473 
Other Countries
 
 
Revenues from External Customers and Long-Lived Assets [Line Items]
 
 
Revenue
$ 691 
$ 703 
Segment and Geographic Information - Long-lived Assets (Details) (USD $)
In Thousands, unless otherwise specified
Sep. 30, 2014
Jun. 30, 2014
Revenues from External Customers and Long-Lived Assets [Line Items]
 
 
Property, plant and equipment, net
$ 120,899 
$ 123,254 
China
 
 
Revenues from External Customers and Long-Lived Assets [Line Items]
 
 
Property, plant and equipment, net
79,262 
80,736 
United States
 
 
Revenues from External Customers and Long-Lived Assets [Line Items]
 
 
Property, plant and equipment, net
41,245 
42,106 
Other Countries
 
 
Revenues from External Customers and Long-Lived Assets [Line Items]
 
 
Property, plant and equipment, net
$ 392 
$ 412 
Segment and Geographic Information - Narratives (Details)
3 Months Ended
Sep. 30, 2014
Segment
Segment Reporting [Abstract]
 
Number of operating segments
1 
Number of reportable segments
1 
Commitments and Contingencies - Purchase Commitments (Details) (USD $)
In Millions, unless otherwise specified
Sep. 30, 2014
Jun. 30, 2014
Raw materials, wafers, and packaging and testing services puchase commitments
 
 
Purchase Commitment, Excluding Long-term Committment [Line Items]
 
 
Purchase commitment, amount
$ 20.6 
$ 34.5 
Property and equipment purchase commitments
 
 
Purchase Commitment, Excluding Long-term Committment [Line Items]
 
 
Purchase commitment, amount
$ 2.5 
$ 4.6 
Commitments and Contingencies - Guarantees (Details) (Indemnification Agreement, USD $)
Sep. 30, 2014
Indemnification Agreement
 
Loss Contingencies [Line Items]
 
Indemnifications accrual
$ 0