Note 7 - Stockholders' Equity (Tables)

6 Months Ended

Jun. 30, 2012

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]

	Three Months Ended June 30,				Six Months Ended June 30,
	2012		2011		2012		2011
Cost of design-to-silicon yield-solutions	$	432	$	522	$	751	$	990
Research and development		251		337		438		680
Selling, general and administrative		636		614		1,035		924
Stock-based compensation expenses	$	1,319	$	1,473	$	2,224	$	2,594

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	Three Months Ended June 30,						Six Months Ended June 30,
	2012			2011			2012			2011
Expected life (in years)		4.87			4.97			4.84			4.94
Volatility		59.5	%		60.8	%		59.6	%		61.0	%
Risk-free interest rate		0.78	%		1.64	%		0.78	%		1.66	%
Expected dividend		—			—			—			—
Weighted average fair value per share of options granted during the period	$	4.32		$	3.21		$	4.21		$	3.17

Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block]

	Six Months Ended June 30,
	2012			2011
Expected life (in years)		1.25			1.25
Volatility		51.1	%		47.2	%
Risk-free interest rate		0.16	%		0.38	%
Expected dividend		—			—
Weighted average fair value of purchase rights granted under the purchase plan	$	2.33		$	2.06

Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]

	Number of Options (in thousands)			Weighted Average Exercise Price per Share		Weighted Average Remaining Contractual Term (years)		Aggregate Intrinsic Value (in thousands)
Outstanding, January 1, 2012		3,872		$	5.91
Granted		1,085			8.52
Exercised		(199	)		4.41
Canceled		(135	)		6.16
Expired		(22	)		7.78
Outstanding, June 30, 2012		4,601			6.58		7.35	$	15,994
Vested and expected to vest, June 30, 2012		4,221			6.53		7.18	$	14,955
Exercisable, June 30, 2012		2,196			6.55		5.58	$	8,138

Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block]

	Shares (in thousands)			Weighted Average Grant Date Fair Value Per Share
Nonvested, January 1, 2012		303		$	7.82
Granted		339			8.71
Vested		(78	)		9.88
Forfeited		(21	)		7.74
Nonvested, June 30, 2012		543			8.08