SBASA61A December   2020  – June 2021 PCM1820 , PCM1821

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: TDM, I2S or LJ Interface
    7. 7.7 Switching Characteristics: TDM, I2S or LJ Interface
    8. 7.8 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 Hardware Control
      2. 8.3.2 Audio Serial Interfaces
        1. 8.3.2.1 Time Division Multiplexed Audio (TDM) Interface
        2. 8.3.2.2 Inter IC Sound (I2S) Interface
      3. 8.3.3 Phase-Locked Loop (PLL) and Clock Generation
      4. 8.3.4 Input Channel Configurations
      5. 8.3.5 Reference Voltage
      6. 8.3.6 Signal-Chain Processing
        1. 8.3.6.1 Digital High-Pass Filter
        2. 8.3.6.2 Configurable Digital Decimation Filters
          1. 8.3.6.2.1 Linear Phase Filters
            1. 8.3.6.2.1.1 Sampling Rate: 8 kHz or 7.35 kHz
            2. 8.3.6.2.1.2 Sampling Rate: 16 kHz or 14.7 kHz
            3. 8.3.6.2.1.3 Sampling Rate: 24 kHz or 22.05 kHz
            4. 8.3.6.2.1.4 Sampling Rate: 32 kHz or 29.4 kHz
            5. 8.3.6.2.1.5 Sampling Rate: 48 kHz or 44.1 kHz
            6. 8.3.6.2.1.6 Sampling Rate: 96 kHz or 88.2 kHz
            7. 8.3.6.2.1.7 Sampling Rate: 192 kHz or 176.4 kHz
          2. 8.3.6.2.2 Low-Latency Filters
            1. 8.3.6.2.2.1 Sampling Rate: 16 kHz or 14.7 kHz
            2. 8.3.6.2.2.2 Sampling Rate: 24 kHz or 22.05 kHz
            3. 8.3.6.2.2.3 Sampling Rate: 32 kHz or 29.4 kHz
            4. 8.3.6.2.2.4 Sampling Rate: 48 kHz or 44.1 kHz
            5. 8.3.6.2.2.5 Sampling Rate: 96 kHz or 88.2 kHz
      7. 8.3.7 Dynamic Range Enhancer (DRE)
    4. 8.4 Device Functional Modes
      1. 8.4.1 Active Mode
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Receiving Notification of Documentation Updates
    2. 12.2 Support Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

8.3.6.1 Digital High-Pass Filter

To remove the DC offset component and attenuate the undesired low-frequency noise content in the record data, the device supports a fixed high-pass filter (HPF) with –3-dB cut-off frequency of 0.00025 × fS. The HPF is not a channel-independent filter but is globally applicable for all the ADC channels. This HPF is constructed using the first-order infinite impulse response (IIR) filter, and is efficient enough to filter out possible DC components of the signal. Table 8-6 shows the fixed –3-dB cutoff frequency value. Figure 8-6 shows a frequency response plot for the HPF filter.

Table 8-6 HPF Cutoff Frequency Value
–3-dB CUTOFF FREQUENCY VALUE -3-dB CUTTOFF FREQUENCY AT 16 kHz SAMPLE RATE -3-dB CUTTOFF FREQUENCY AT 48 kHz SAMPLE RATE
0.00025 × fS 4 Hz 12 Hz

 

GUID-B1131061-96D2-4594-A27A-F0ADED93018E-low.gifFigure 8-6 HPF Filter Frequency Response Plot