SBAU359A May   2019  – June 2021

 

  1.   Trademarks
  2. 1Introduction
  3. 2Hardware Overview
    1. 2.1 AC-MB Settings
      1. 2.1.1 Audio Serial Interface Settings
        1. 2.1.1.1 USB
        2. 2.1.1.2 Optical or Auxilary Analog Audio Input
        3. 2.1.1.3 External
      2. 2.1.2 AC-MB Power Supply
    2. 2.2 ADCx120EVM-PDK Hardware Settings
      1. 2.2.1 Line Inputs
      2. 2.2.2 Onboard Microphone Configuration
      3. 2.2.3 External Microphone Configurations
  4. 3Software Overview
    1. 3.1 PurePath Console 3 Installation
    2. 3.2 ADCx120EVM GUI Installation
      1. 3.2.1 Software Setup
  5. 4GPIO1 Settings
  6. 5Master Mode Operation
  7. 6Quick Start
    1. 6.1 Configuring the Audio Serial Bus for the I2S Output
    2. 6.2 Saving a Configuration
  8. 7Schematic and Bill of Materials
    1. 7.1 ADCx120EVM-PDK Schematic and Bill of Materials
      1. 7.1.1 ADCx120EVM-PDK Schematic
      2. 7.1.2 ADCx120EVM-PDK Bill of Materials
    2. 7.2 AC-MB Schematic and Bill of Materials
      1. 7.2.1 AC-MB Schematic
      2. 7.2.2 AC-MB Bill of Materials
    3. 7.3 Matlab Audio Capture Example
  9. 8Revision History

2.2.3 External Microphone Configurations

The TLV320ADCx120 family of devices support both analog and digital PDM inputs with up to 2 channels of analog input or 4 channels of digital PDM input. It is also possible to use various combinations of analog and digital inputs with up to 2 analog inputs and 2 digital inputs operating simultaneously.

Single-ended or differential analog inputs can be applied on the following pin pairs: IN1P, IN1M, IN2P_GPI1, IN2M_GPO1.

Digital PDM inputs can be applied to the following pins: IN2P_GPI1, MICBIAS_GPI2, GPIO1. A PDM clock can also be output on pins: IN2M_GPO1, GPIO1.

On the EVM access to these pins is provided on terminals J1, J2, J3, and J10. Figure 2-10, Figure 2-11, and Figure 2-12 illustrate the recommended pin connections for common use-cases.

Note, the GPIO1 pin is referenced to the IOVDD domain while IN2P_GPI1, MICBIAS_GPI2, and IN2M_GPO1 are all referenced to AVDD. Thus, if using 2 analog mics in addition to digital mics it is recommended that AVDD and IOVDD be set to the same voltage or a level translator be placed between GPIO1 and the digital microphone. If only 1 analog mic is used then it is recommended to use IN1P and IN1M for the analog mic. If digital mics are used, it is recommended to use IN2M_GPO1 to generate the PDMCLK signal.

GUID-20201215-CA0I-LK13-1PN4-PPZWFZ5K71PP-low.gifFigure 2-10 External Mics: 2x Analog Microphones
GUID-20201215-CA0I-8W8S-D8TN-49NBQX2M8HB9-low.gifFigure 2-11 External Mics: 4x Digital Microphones
GUID-20201215-CA0I-RXW8-B9D4-LN7WMTGVWB3B-low.gifFigure 2-12 External Mics: 2x Analog and 2x Digital Microphones