MICROSEMI CORPORATION

Schedule Reconciling Selected Non-GAAP Financial Measures

to Comparable GAAP Financial Measures

(unaudited, in millions, except for per share amounts)

Quarter Ended

Six Months Ended

Mar 31,
2013

Dec 30,
2012

Apr 1,
2012

Mar 31,
2013

Apr 1,
2012

GAAP gross profit

$

133.5

$

142.6

$

131.9

$

276.1

$

257.6

Manufacturing profit in acquired inventory (1)

—

—

2.0

—

8.1

Thailand flood-related charges (3)

—

—

3.2

—

3.2

Non-GAAP gross profit

$

133.5

$

142.6

$

137.1

$

276.1

$

268.9

GAAP operating income

$

11.8

$

25.5

$

11.1

$

37.3

$

10.4

Adjustments to GAAP gross profit

—

—

5.2

—

11.3

Restructuring and other special charges (2)

6.9

1.4

1.6

8.3

9.5

Amortization of intangible assets (3)

21.1

21.7

26.6

42.8

51.3

Stock based compensation (4)

10.2

8.1

10.0

18.3

17.6

Acquisition costs (5)

—

—

0.4

—

6.6

Non-GAAP operating income

$

50.0

$

56.7

$

54.9

$

106.7

$

106.7

GAAP net income (loss)

$

(2.9)

$

14.2

$

(4.8)

$

11.3

$

(49.5)

Adjustments to GAAP gross profit and operating income

38.2

31.2

43.8

69.4

96.3

Loss from facility closure and asset disposal (2)

0.2

—

—

0.2

1.6

Thailand flood-related charges (2)

—

—

(0.3)

—

1.5

Credit facility issuance and refinancing costs (6)

3.3

0.3

1.5

3.6

35.6

(Gain) in debt and derivative instruments (7)

(0.3)

(0.3)

(0.1)

(0.6)

(5.1)

Income tax effect on non-GAAP adjustments (8)

0.4

(0.4)

0.2

—

(6.5)

Non-GAAP net income

$

38.9

$

45.0

$

40.3

$

83.9

$

73.9

GAAP diluted earnings (loss) per share

$

(0.03)

$

0.16

$

(0.06)

$

0.12

$

(0.58)

Effect of non-GAAP adjustments on diluted earnings per share

$

0.46

$

0.34

$

0.52

$

0.81

$

1.43

Non-GAAP diluted earnings per share

$

0.43

$

0.50

$

0.46

$

0.93

$

0.85

Weighted average diluted shares used in calculating non-GAAP diluted earnings per share

91.1

90.1

87.5

90.5

86.7