Microchip Technology AC164129 사용자 매뉴얼

차례

• Introduction

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• Document Layout

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• Conventions Used in this Guide

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• Warranty Registration

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• Recommended Reading

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• The Microchip Web Site

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• Development Systems Customer Change Notification Service

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• Customer Support

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• Document Revision History

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• Chapter 1. Introduction

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• 1.1 Overview

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  • Figure 1-1: AUDIO PICtail™ PLUS DAUGHTER BOARD

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• 1.2 Board Setup

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  • Figure 1-2: AUDIO PICtail™ PLUS DAUGHTER BOARD Setup

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• 1.3 Reference Documents

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• Chapter 2. Hardware

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• 2.1 Functional Overview

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  • Figure 2-1: AUDIO PICtail™ PLUS DAUGHTER BOARD Block Diagram

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  • 2.1.1 Speech Sampling

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  • 2.1.2 Speech Playback

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    • Figure 2-2: PWM Demodulation

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  • 2.1.3 Codec

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  • 2.1.4 DAC Differential Amplifier

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  • 2.1.5 4-Mb Serial Flash Memory

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• 2.2 Hardware Components

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  • Figure 2-3: AUDIO PICtail™ PLUS DAUGHTER BOARD

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  • 2.2.1 Line/Microphone Input Phone Jack (J1)

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  • 2.2.2 Line/Microphone Input Select Jumper (J8)

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  • 2.2.3 Line/Microphone Pre-Amplifier (U4:A)

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    • Equation 2-1: Input Pre-Amplifier Gain

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  • 2.2.4 Anti-Aliasing Low-Pass Filter (U4:C)

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  • 2.2.5 Microphone Gain Control (R29)

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  • 2.2.6 ADC Channel Select Jumper (J5)

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  • 2.2.7 PWM Low-Pass Filter (U3:A,B)

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  • 2.2.8 Filter Input Select Jumper (J7)

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  • 2.2.9 Output Select Jumper (J4)

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  • 2.2.10 Line Output Amplifier (U4:B)

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    • Equation 2-2: Line Output Amplifier Gain

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  • 2.2.11 Line Output Gain Control Potentiometer (R24)

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  • 2.2.12 Line Output Jack (J9)

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  • 2.2.13 Headphone Amplifier (U5)

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  • 2.2.14 Headphone Amplifier Digital Volume Control

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  • 2.2.15 Headphone Output Jack (J10)

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  • 2.2.16 DAC Differential Amplifier (U3:C)

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  • 2.2.17 Codec (U2)

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  • 2.2.18 Codec Oscillator (Y1)

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  • 2.2.19 Flash Memory (U1)

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  • 2.2.20 Flash Memory Write-Protect Jumper (J6)

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  • 2.2.21 Explorer 16 PICtail Connector (J2)

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  • 2.2.22 28-Pin Starter Development Board Connector (J3)

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• Chapter 3. PWM Speech Loopback Demo

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• 3.1 Speech Loopback Demo

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  • Figure 3-1: Speech Loopback Demo Overview

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  • 3.1.1 ADC Driver

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  • 3.1.2 Output Compare Module Driver

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  • 3.1.3 Loopback Application Software

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    • Figure 3-2: Application Flow Chart

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• 3.2 Running the Demo

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• Appendix A. Drawings and Schematics

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• A.1 Audio PICtail Plus Daughter Board Layout

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  • Figure A-1: AUDIO PICtail™ PLUS DAUGHTER BOARD Layout

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• A.2 Schematic Diagrams

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  • Figure A-2: Speech Sampling Interface Schematic

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  • Figure A-3: Anti-Aliasing Low-Pass Filter Schematic

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  • Figure A-4: Speech Playback Interface Schematic

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  • Figure A-5: Codec Schematic

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  • Figure A-6: Flash Memory Schematic

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  • Figure A-7: Board Connectors

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