データシート目次Introduction5Document Layout5Conventions Used in this Guide6Warranty Registration7Recommended Reading7The Microchip Web Site8Development Systems Customer Change Notification Service9Customer Support9Document Revision History10Chapter 1. Introduction111.1 Overview11Figure 1-1: AUDIO PICtail™ PLUS DAUGHTER BOARD121.2 Board Setup12Figure 1-2: AUDIO PICtail™ PLUS DAUGHTER BOARD Setup121.3 Reference Documents13Chapter 2. Hardware152.1 Functional Overview15Figure 2-1: AUDIO PICtail™ PLUS DAUGHTER BOARD Block Diagram152.1.1 Speech Sampling152.1.2 Speech Playback16Figure 2-2: PWM Demodulation162.1.3 Codec162.1.4 DAC Differential Amplifier162.1.5 4-Mb Serial Flash Memory172.2 Hardware Components17Figure 2-3: AUDIO PICtail™ PLUS DAUGHTER BOARD172.2.1 Line/Microphone Input Phone Jack (J1)182.2.2 Line/Microphone Input Select Jumper (J8)182.2.3 Line/Microphone Pre-Amplifier (U4:A)18Equation 2-1: Input Pre-Amplifier Gain182.2.4 Anti-Aliasing Low-Pass Filter (U4:C)182.2.5 Microphone Gain Control (R29)182.2.6 ADC Channel Select Jumper (J5)182.2.7 PWM Low-Pass Filter (U3:A,B)192.2.8 Filter Input Select Jumper (J7)192.2.9 Output Select Jumper (J4)192.2.10 Line Output Amplifier (U4:B)19Equation 2-2: Line Output Amplifier Gain192.2.11 Line Output Gain Control Potentiometer (R24)192.2.12 Line Output Jack (J9)202.2.13 Headphone Amplifier (U5)202.2.14 Headphone Amplifier Digital Volume Control202.2.15 Headphone Output Jack (J10)202.2.16 DAC Differential Amplifier (U3:C)202.2.17 Codec (U2)202.2.18 Codec Oscillator (Y1)212.2.19 Flash Memory (U1)212.2.20 Flash Memory Write-Protect Jumper (J6)212.2.21 Explorer 16 PICtail Connector (J2)212.2.22 28-Pin Starter Development Board Connector (J3)21Chapter 3. PWM Speech Loopback Demo233.1 Speech Loopback Demo23Figure 3-1: Speech Loopback Demo Overview233.1.1 ADC Driver243.1.2 Output Compare Module Driver243.1.3 Loopback Application Software25Figure 3-2: Application Flow Chart253.2 Running the Demo26Appendix A. Drawings and Schematics27A.1 Audio PICtail Plus Daughter Board Layout27Figure A-1: AUDIO PICtail™ PLUS DAUGHTER BOARD Layout27A.2 Schematic Diagrams27Figure A-2: Speech Sampling Interface Schematic28Figure A-3: Anti-Aliasing Low-Pass Filter Schematic28Figure A-4: Speech Playback Interface Schematic29Figure A-5: Codec Schematic30Figure A-6: Flash Memory Schematic30Figure A-7: Board Connectors31サイズ: 2.28MBページ数: 34Language: Englishマニュアルを開く