SBASB79 November   2024 TAA3020

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1  Absolute Maximum Ratings
    2. 5.2  ESD Ratings
    3. 5.3  Recommended Operating Conditions
    4. 5.4  Thermal Information
    5. 5.5  Electrical Characteristics
    6. 5.6  Timing Requirements: I2C Interface
    7. 5.7  Switching Characteristics: I2C Interface
    8. 5.8  Timing Requirements: TDM, I2S or LJ Interface
    9. 5.9  Switching Characteristics: TDM, I2S or LJ Interface
    10. 5.10 Timing Requirements: PDM Digital Microphone Interface
    11. 5.11 Switching Characteristics: PDM Digial Microphone Interface
    12. 5.12 Timing Diagrams
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1  Serial Interfaces
        1. 6.3.1.1 Control Serial Interfaces
        2. 6.3.1.2 Audio Serial Interfaces
          1. 6.3.1.2.1 Time Division Multiplexed Audio (TDM) Interface
          2. 6.3.1.2.2 Inter IC Sound (I2S) Interface
          3. 6.3.1.2.3 Left-Justified (LJ) Interface
        3. 6.3.1.3 Using Multiple Devices With Shared Buses
      2. 6.3.2  Phase-Locked Loop (PLL) and Clock Generation
      3. 6.3.3  Input Channel Configurations
      4. 6.3.4  Reference Voltage
      5. 6.3.5  Programmable Microphone Bias
      6. 6.3.6  Signal-Chain Processing
        1. 6.3.6.1 Programmable Channel Gain and Digital Volume Control
        2. 6.3.6.2 Programmable Channel Gain Calibration
        3. 6.3.6.3 Programmable Channel Phase Calibration
        4. 6.3.6.4 Programmable Digital High-Pass Filter
        5. 6.3.6.5 Programmable Digital Biquad Filters
        6. 6.3.6.6 Programmable Channel Summer and Digital Mixer
        7. 6.3.6.7 Configurable Digital Decimation Filters
          1. 6.3.6.7.1 Linear Phase Filters
            1. 6.3.6.7.1.1 Sampling Rate: 7.35 kHz to 8 kHz
            2. 6.3.6.7.1.2 Sampling Rate: 14.7 kHz to 16 kHz
            3. 6.3.6.7.1.3 Sampling Rate: 22.05 kHz to 24 kHz
            4. 6.3.6.7.1.4 Sampling Rate: 29.4 kHz to 32 kHz
            5. 6.3.6.7.1.5 Sampling Rate: 44.1 kHz to 48 kHz
            6. 6.3.6.7.1.6 Sampling Rate: 88.2 kHz to 96 kHz
            7. 6.3.6.7.1.7 Sampling Rate: 176.4 kHz to 192 kHz
            8. 6.3.6.7.1.8 Sampling Rate: 352.8 kHz to 384 kHz
            9. 6.3.6.7.1.9 Sampling Rate: 705.6 kHz to 768 kHz
          2. 6.3.6.7.2 Low-Latency Filters
            1. 6.3.6.7.2.1 Sampling Rate: 14.7 kHz to 16 kHz
            2. 6.3.6.7.2.2 Sampling Rate: 22.05 kHz to 24 kHz
            3. 6.3.6.7.2.3 Sampling Rate: 29.4 kHz to 32 kHz
            4. 6.3.6.7.2.4 Sampling Rate: 44.1 kHz to 48 kHz
            5. 6.3.6.7.2.5 Sampling Rate: 88.2 kHz to 96 kHz
            6. 6.3.6.7.2.6 Sampling Rate: 176.4 kHz to 192 kHz
          3. 6.3.6.7.3 Ultra-Low Latency Filters
            1. 6.3.6.7.3.1 Sampling Rate: 14.7 kHz to 16 kHz
            2. 6.3.6.7.3.2 Sampling Rate: 22.05 kHz to 24 kHz
            3. 6.3.6.7.3.3 Sampling Rate: 29.4 kHz to 32 kHz
            4. 6.3.6.7.3.4 Sampling Rate: 44.1 kHz to 48 kHz
            5. 6.3.6.7.3.5 Sampling Rate: 88.2 kHz to 96 kHz
            6. 6.3.6.7.3.6 Sampling Rate: 176.4 kHz to 192 kHz
            7. 6.3.6.7.3.7 Sampling Rate: 352.8 kHz to 384 kHz
      7. 6.3.7  Automatic Gain Controller (AGC)
      8. 6.3.8  Voice Activity Detection (VAD)
      9. 6.3.9  Digital PDM Microphone Record Channel
      10. 6.3.10 Interrupts, Status, and Digital I/O Pin Multiplexing
    4. 6.4 Device Functional Modes
      1. 6.4.1 Sleep Mode or Software Shutdown
      2. 6.4.2 Active Mode
      3. 6.4.3 Software Reset
    5. 6.5 Programming
      1. 6.5.1 Control Serial Interfaces
        1. 6.5.1.1 I2C Control Interface
          1. 6.5.1.1.1 General I2C Operation
            1. 6.5.1.1.1.1 I2C Single-Byte and Multiple-Byte Transfers
              1. 6.5.1.1.1.1.1 I2C Single-Byte Write
              2. 6.5.1.1.1.1.2 I2C Multiple-Byte Write
              3. 6.5.1.1.1.1.3 I2C Single-Byte Read
              4. 6.5.1.1.1.1.4 I2C Multiple-Byte Read
  8. 7 Register Maps
    1. 7.1 Device Configuration Registers
    2. 7.2 Page_0 Registers
    3. 7.3 Page_1 Registers
    4. 7.4 Programmable Coefficient Registers
      1. 7.4.1 Programmable Coefficient Registers: Page 2
      2. 7.4.2 Programmable Coefficient Registers: Page 3
      3. 7.4.3 Programmable Coefficient Registers: Page 4
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Two-Channel Analog Microphone Recording
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Example Device Register Configuration Script for EVM Setup
      2. 8.2.2 Four-Channel Digital PDM Microphone Recording
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
          1. 8.2.2.2.1 Example Device Register Configuration Script for EVM Setup
    3. 8.3 What to Do and What Not to Do
    4. 8.4 Power Supply Recommendations
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
      2. 8.5.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Documentation Support
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information
    1. 11.1 Package Option Addendum
    2. 11.2 Tape and Reel Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

6.3.7 Automatic Gain Controller (AGC)

The device includes an automatic gain controller (AGC) for ADC recording. As shown in Figure 6-63, the AGC can be used to maintain a nominally constant output level when recording speech. Instead of manually setting the channel gain in AGC mode, the circuitry automatically adjusts the channel gain when the input signal becomes overly loud or very weak, such as when a person speaking into a microphone moves closer to or farther from the microphone. The AGC algorithm has several programmable parameters, including target level, maximum gain allowed, attack and release (or decay) time constants, and noise thresholds that allow the algorithm to be fine-tuned for any particular application.

TAA3020 AGC Characteristics Figure 6-63 AGC Characteristics

The target level (AGC_LVL) represents the nominal approximate output level at which the AGC attempts to hold the ADC output signal level. The TAA3020 allows programming of different target levels, which can be programmed from –6 dB to –36 dB relative to a full-scale signal, and the AGC_LVL default value is set to –34 dB. The target level is recommended to be set with enough margin to prevent clipping when loud sounds occur. Table 6-45 lists the AGC target level configuration settings.

Table 6-45 AGC Target Level Programmable Settings
P0_R112_D[7:4] : AGC_LVL[3:0] AGC TARGET LEVEL FOR OUTPUT
0000 The AGC target level is the –6-dB output signal level
0001 The AGC target level is the –8-dB output signal level
0010 The AGC target level is the –10-dB output signal level
… …
1110 (default) The AGC target level is the –34-dB output signal level
1111 The AGC target level is the –36-dB output signal level

The maximum gain allowed (AGC_MAXGAIN) gives flexibility to the designer to restrict the maximum gain applied by the AGC. This feature limits the channel gain in situations where environmental noise is greater than the programmed noise threshold. The AGC_MAXGAIN can be programmed from 3 dB to 42 dB with steps of 3 dB and the default value is set to 24 dB. Table 6-46 lists the AGC_MAXGAIN configuration settings.

Table 6-46 AGC Maximum Gain Programmable Settings
P0_R112_D[3:0] : AGC_MAXGAIN[3:0] AGC MAXIMUM GAIN ALLOWED
0000 The AGC maximum gain allowed is 3 dB
0001 The AGC maximum gain allowed is 6 dB
0010 The AGC maximum gain allowed is 9 dB
… …
0111 (default) The AGC maximum gain allowed is 24 dB
… …
1110 The AGC maximum gain allowed is 39 dB
1111 The AGC maximum gain allowed is 42 dB

For further details on the AGC various configurable parameter and application use, see the Using the Automatic Gain Controller (AGC) in TLV320ADCx120 Family application report.