SBAS989 April   2019 PCM1840

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Simplified Block Diagram
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Timing Requirements: TDM, I2S or LJ Interface
    7. 6.7 Switching Characteristics: TDM, I2S or LJ Interface
    8. 6.8 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Hardware Control
      2. 7.3.2 Audio Serial Interfaces
        1. 7.3.2.1 Time Division Multiplexed Audio (TDM) Interface
        2. 7.3.2.2 Inter IC Sound (I2S) Interface
        3. 7.3.2.3 Left-Justified (LJ) Interface
      3. 7.3.3 Phase-Locked Loop (PLL) and Clock Generation
      4. 7.3.4 Input Channel Configurations
      5. 7.3.5 Reference Voltage
      6. 7.3.6 Microphone Bias
      7. 7.3.7 Signal-Chain Processing
        1. 7.3.7.1 Digital High-Pass Filter
        2. 7.3.7.2 Configurable Digital Decimation Filters
          1. 7.3.7.2.1 Linear Phase Filters
            1. 7.3.7.2.1.1 Sampling Rate: 8 kHz or 7.35 kHz
            2. 7.3.7.2.1.2 Sampling Rate: 16 kHz or 14.7 kHz
            3. 7.3.7.2.1.3 Sampling Rate: 24 kHz or 22.05 kHz
            4. 7.3.7.2.1.4 Sampling Rate: 32 kHz or 29.4 kHz
            5. 7.3.7.2.1.5 Sampling Rate: 48 kHz or 44.1 kHz
            6. 7.3.7.2.1.6 Sampling Rate: 96 kHz or 88.2 kHz
            7. 7.3.7.2.1.7 Sampling Rate: 192 kHz or 176.4 kHz
          2. 7.3.7.2.2 Low-Latency Filters
            1. 7.3.7.2.2.1 Sampling Rate: 16 kHz or 14.7 kHz
            2. 7.3.7.2.2.2 Sampling Rate: 24 kHz or 22.05 kHz
            3. 7.3.7.2.2.3 Sampling Rate: 32 kHz or 29.4 kHz
            4. 7.3.7.2.2.4 Sampling Rate: 48 kHz or 44.1 kHz
            5. 7.3.7.2.2.5 Sampling Rate: 96 kHz or 88.2 kHz
      8. 7.3.8 Dynamic Range Enhancer (DRE)
    4. 7.4 Device Functional Modes
      1. 7.4.1 Hardware Shutdown
      2. 7.4.2 Active Mode
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Receiving Notification of Documentation Updates
    2. 11.2 Community Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7.3.2 Audio Serial Interfaces

Digital audio data flows between the host processor and the PCM1840 on the digital audio serial interface (ASI), or audio bus. This highly flexible ASI bus includes a TDM mode for multichannel operation, support for I2S or left-justified protocols format, and the pin-selectable master-slave configurability for bus clock lines.

The device supports audio bus master or slave mode of operation using the hardware pin MSZ. In slave mode, FSYNC and BCLK work as input pins whereas in master mode, FSYNC and BCLK work as output pins generated by the device.Table 1 shows the master and slave mode selection using the MSZ pin.

Table 1. Master and Slave Mode Selection

MSZ MASTER AND SLAVE SELECTION
LOW Slave mode of operation
HIGH Master ode of operation

The bus protocol TDM, I2S, or left-justified (LJ) format can be selected by using the FMT0 and FMT1 pins. As shown in Table 2, these modes are all most significant byte (MSB)-first, pulse code modulation (PCM) data format, with the output channel data word-length of 32 bits.

Table 2. Audio Serial Interface Format

FMT1 FMT0 AUDIO SERIAL INTERFACE FORMAT
LOW LOW 4-channel output with time division multiplexing (TDM) mode
LOW HIGH 2-channel output with time division multiplexing (TDM) mode
HIGH LOW 2-channel output with left-justified (LJ) mode
HIGH HIGH 2-channel output with inter IC sound (I2S) mode