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AS3421 AS3422

Datasheet - C o n t e n t s

4 Contents

1 General Description ..................................................................................................................................................................

1

2 Key Features.............................................................................................................................................................................

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3 Applications...............................................................................................................................................................................

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4 Contents....................................................................................................................................................................................

3

5 Pin Assignments .......................................................................................................................................................................

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5.1 Pin Descriptions....................................................................................................................................................................................

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6 Absolute Maximum Ratings ......................................................................................................................................................

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7 Electrical Characteristics...........................................................................................................................................................

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8 Typical Operating Characteristics .............................................................................................................................................

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9 Detailed Description

................................................................................................................................................................11

9.1 Audio Line Input

................................................................................................................................................................................. 11

9.2 Microphone Input

............................................................................................................................................................................... 12

9.3 Headphone Output

............................................................................................................................................................................. 14

9.4 Operational Amplifier

.......................................................................................................................................................................... 15

9.5 SYSTEM

............................................................................................................................................................................................ 17

9.6 VNEG Charge Pump

.......................................................................................................................................................................... 20

9.7 OTP Memory & Internal Registers

..................................................................................................................................................... 20

9.8 2-Wire-Serial Control Interface

........................................................................................................................................................... 23

10 Register Description

............................................................................................................................................................. 27

11 Application Information

......................................................................................................................................................... 43

11.1 AS3422 Feedback Application Examples

........................................................................................................................................ 43

11.2 AS3421 Feed Forward Application Examples

.................................................................................................................................. 47

11.3 Layout Recommendation

................................................................................................................................................................ 51

11.4 Bill of Materials

................................................................................................................................................................................ 52

11.5 PCB Footprint Recommendation

...................................................................................................................................................... 53

12 Package Drawings and Marking .............................................................................................................................. .................55

Ordering Information

....................................................................................................................................................................59