SBASA30 December   2020 PCM6480-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1  Absolute Maximum Ratings
    2. 7.2  ESD Ratings
    3. 7.3  Recommended Operating Conditions
    4. 7.4  Thermal Information
    5. 7.5  Electrical Characteristics
    6. 7.6  Timing Requirements: I2C Interface
    7. 7.7  Switching Characteristics: I2C Interface
    8. 7.8  Timing Requirements: SPI Interface
    9. 7.9  Switching Characteristics: SPI Interface
    10. 7.10 Timing Requirements: TDM, I2S or LJ Interface
    11. 7.11 Switching Characteristics: TDM, I2S or LJ Interface
    12. 7.12 Timing Requirements: PDM Digital Microphone Interface
    13. 7.13 Switching Characteristics: PDM Digial Microphone Interface
    14. 7.14 Timing Diagrams
    15. 7.15 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Serial Interfaces
        1. 8.3.1.1 Control Serial Interfaces
        2. 8.3.1.2 Audio Serial Interfaces
          1. 8.3.1.2.1 Time Division Multiplexed Audio (TDM) Interface
          2. 8.3.1.2.2 Inter IC Sound (I2S) Interface
          3. 8.3.1.2.3 Left-Justified (LJ) Interface
        3. 8.3.1.3 Using Multiple Devices With Shared Buses
      2. 8.3.2  Phase-Locked Loop (PLL) and Clock Generation
      3. 8.3.3  Analog Input Channel Configuration
      4. 8.3.4  Reference Voltage
      5. 8.3.5  Microphone Bias
      6. 8.3.6  Input DC Fault Diagnostics
        1. 8.3.6.1 Fault Conditions
          1. 8.3.6.1.1 Input Pin Short to Ground
          2. 8.3.6.1.2 Input Pin Short to MICBIAS
          3. 8.3.6.1.3 Open Inputs
          4. 8.3.6.1.4 Short Between INxP and INxM
          5. 8.3.6.1.5 Input Pin Overvoltage
          6. 8.3.6.1.6 Input Pin Short to VBAT_IN
        2. 8.3.6.2 Fault Reporting
          1. 8.3.6.2.1 Overcurrent and Overtemperature Protection
      7. 8.3.7  Digital PDM Microphone Record Channel
      8. 8.3.8  Signal-Chain Processing
        1. 8.3.8.1 Programmable Channel Gain and Digital Volume Control
        2. 8.3.8.2 Programmable Channel Gain Calibration
        3. 8.3.8.3 Programmable Channel Phase Calibration
        4. 8.3.8.4 Programmable Digital High-Pass Filter
        5. 8.3.8.5 Programmable Digital Biquad Filters
        6. 8.3.8.6 Programmable Channel Summer and Digital Mixer
        7. 8.3.8.7 Configurable Digital Decimation Filters
          1. 8.3.8.7.1 Linear Phase Filters
            1. 8.3.8.7.1.1 Sampling Rate: 8 kHz or 7.35 kHz
            2. 8.3.8.7.1.2 Sampling Rate: 16 kHz or 14.7 kHz
            3. 8.3.8.7.1.3 Sampling Rate: 24 kHz or 22.05 kHz
            4. 8.3.8.7.1.4 Sampling Rate: 32 kHz or 29.4 kHz
            5. 8.3.8.7.1.5 Sampling Rate: 48 kHz or 44.1 kHz
            6. 8.3.8.7.1.6 Sampling Rate: 96 kHz or 88.2 kHz
            7. 8.3.8.7.1.7 Sampling Rate: 192 kHz or 176.4 kHz
            8. 8.3.8.7.1.8 Sampling Rate: 384 kHz or 352.8 kHz
            9. 8.3.8.7.1.9 Sampling Rate: 768 kHz or 705.6 kHz
          2. 8.3.8.7.2 Low-Latency Filters
            1. 8.3.8.7.2.1 Sampling Rate: 16 kHz or 14.7 kHz
            2. 8.3.8.7.2.2 Sampling Rate: 24 kHz or 22.05 kHz
            3. 8.3.8.7.2.3 Sampling Rate: 32 kHz or 29.4 kHz
            4. 8.3.8.7.2.4 Sampling Rate: 48 kHz or 44.1 kHz
            5. 8.3.8.7.2.5 Sampling Rate: 96 kHz or 88.2 kHz
            6. 8.3.8.7.2.6 Sampling Rate: 192 kHz or 176.4 kHz
          3. 8.3.8.7.3 Ultra-Low-Latency Filters
            1. 8.3.8.7.3.1 Sampling Rate: 16 kHz or 14.7 kHz
            2. 8.3.8.7.3.2 Sampling Rate: 24 kHz or 22.05 kHz
            3. 8.3.8.7.3.3 Sampling Rate: 32 kHz or 29.4 kHz
            4. 8.3.8.7.3.4 Sampling Rate: 48 kHz or 44.1 kHz
            5. 8.3.8.7.3.5 Sampling Rate: 96 kHz or 88.2 kHz
            6. 8.3.8.7.3.6 Sampling Rate: 192 kHz or 176.4 kHz
            7. 8.3.8.7.3.7 Sampling Rate: 384 kHz or 352.8 kHz
      9. 8.3.9  Automatic Gain Controller (AGC)
      10. 8.3.10 Interrupts, Status, and Digital I/O Pin Multiplexing
    4. 8.4 Device Functional Modes
      1. 8.4.1 Hardware Shutdown
      2. 8.4.2 Sleep Mode or Software Shutdown
      3. 8.4.3 Active Mode
      4. 8.4.4 Software Reset
    5. 8.5 Programming
      1. 8.5.1 Control Serial Interfaces
        1. 8.5.1.1 I2C Control Interface
          1. 8.5.1.1.1 General I2C Operation
          2. 8.5.1.1.2 I2C Single-Byte and Multiple-Byte Transfers
            1. 8.5.1.1.2.1 I2C Single-Byte Write
            2. 8.5.1.1.2.2 I2C Multiple-Byte Write
            3. 8.5.1.1.2.3 I2C Single-Byte Read
            4. 8.5.1.1.2.4 I2C Multiple-Byte Read
        2. 8.5.1.2 SPI Control Interface
    6. 8.6 Register Maps
      1. 8.6.1 Device Configuration Registers
        1. 8.6.1.1 Registers Access Type
        2. 8.6.1.2 Page 0 Registers
        3. 8.6.1.3 Page 1 Registers
      2. 8.6.2 Programmable Coefficient Registers
        1. 8.6.2.1 Programmable Coefficient Registers: Page 2
        2. 8.6.2.2 Programmable Coefficient Registers: Page 3
        3. 8.6.2.3 Programmable Coefficient Registers: Page 4
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Four-Channel Analog Microphone and Four-Channel PDM Microphone Simultaneous Recording Using the PCM6480-Q1
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Example Device Register Configuration Script for EVM Setup
        3. 9.2.1.3 Application Curves
    3. 9.3 What To Do and What Not To Do
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Development Support
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 Support Resources
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

8.3.9 Automatic Gain Controller (AGC)

The device includes an automatic gain controller (AGC) for ADC recording that must be used only for the AC-coupled input configuration. As shown in Figure 8-69, 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.

GUID-278960F3-B360-429D-850A-F843519C446D-low.gifFigure 8-69 AGC Characteristics

The target level (AGC_LVL) represents the nominal output level at which the AGC attempts to hold the ADC output signal level. The PCM6480-Q1 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 8-42 lists the AGC target level configuration settings.

Table 8-42 AGC Target Level Programmable Settings
P0_R112_D[7:4] : AGC_LVL[3:0]AGC TARGET LEVEL FOR OUTPUT
0000The AGC target level is the –6-dB output signal level
0001The AGC target level is the –8-dB output signal level
0010The AGC target level is the –10-dB output signal level
……
1110 (default)The AGC target level is the –34-dB output signal level
1111The 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 8-43 lists the AGC_MAXGAIN configuration settings.

Table 8-43 AGC Maximum Gain Programmable Settings
P0_R112_D[3:0] : AGC_MAXGAIN[3:0]AGC MAXIMUM GAIN ALLOWED
0000The AGC maximum gain allowed is 3 dB
0001The AGC maximum gain allowed is 6 dB
0010The AGC maximum gain allowed is 9 dB
……
0111 (default)The AGC maximum gain allowed is 24 dB
……
1110The AGC maximum gain allowed is 39 dB
1111The 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 in PCM6xx0-Q1 application report.