SLAS763C August   2012  – October 2018 PCM5121 , PCM5122

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified System Diagram
  4. 4 Revision History
  5. 5 Device Comparison
  6. 6 Pin Configuration and Functions
    1. 6.0.1 RHB Package I2C Mode (MODE1 tied to DGND and MODE2 tied to DVDD) Top View
    2. 6.0.2 RHB Package SPI Mode (MODE1 tied to DVDD) Top View
    3. 6.0.3 RHB Package Hardwired Mode (MODE1 tied to DGND, MODE2 tied to DGND) Top View
    4.     Pin 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: SCK Input
    7. 7.7 Timing Requirements: XSMT
    8. 7.8 Switching Characteristics
    9. 7.9 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 Terminology
      2. 8.3.2 Audio Data Interface
        1. 8.3.2.1 Audio Serial Interface
        2. 8.3.2.2 PCM Audio Data Formats
        3. 8.3.2.3 Zero Data Detect
      3. 8.3.3 XSMT Pin (Soft Mute / Soft Un-Mute)
      4. 8.3.4 Audio Processing
        1. 8.3.4.1 PCM512x Audio Processing
          1. 8.3.4.1.1 Overview
          2. 8.3.4.1.2 Software
        2. 8.3.4.2 Interpolation Filter
        3. 8.3.4.3 Fixed Audio Processing Flow (Program 5)
          1. 8.3.4.3.1 Filter Programming Changes
          2. 8.3.4.3.2 Processing Blocks – Detailed Descriptions
          3. 8.3.4.3.3 Biquad Section
          4. 8.3.4.3.4 Dynamic Range Compression
          5. 8.3.4.3.5 Stereo Mixer
          6. 8.3.4.3.6 Stereo Multiplexer
          7. 8.3.4.3.7 Mono Mixer
          8. 8.3.4.3.8 Master Volume Control
          9. 8.3.4.3.9 Miscellaneous Coefficients
      5. 8.3.5 DAC Outputs
        1. 8.3.5.1 Analog Outputs
        2. 8.3.5.2 Recommended Output Filter for the PCM512x
        3. 8.3.5.3 Choosing Between VREF and VCOM Modes
          1. 8.3.5.3.1 Voltage Reference and Output Levels
          2. 8.3.5.3.2 Mode Switching Sequence, from VREF Mode to VCOM Mode
        4. 8.3.5.4 Digital Volume Control
          1. 8.3.5.4.1 Emergency Ramp-Down
        5. 8.3.5.5 Analog Gain Control
      6. 8.3.6 Reset and System Clock Functions
        1. 8.3.6.1 Clocking Overview
        2. 8.3.6.2 Clock Slave Mode With Master and System Clock (SCK) Input (4 Wire I2S)
        3. 8.3.6.3 Clock Slave Mode With BCK PLL to Generate Internal Clocks (3-Wire PCM)
        4. 8.3.6.4 Clock Generation Using the PLL
        5. 8.3.6.5 PLL Calculation
          1. 8.3.6.5.1 Examples:
            1. 8.3.6.5.1.1 Recommended PLL Settings
        6. 8.3.6.6 Clock Master Mode from Audio Rate Master Clock
        7. 8.3.6.7 Clock Master from a Non-Audio Rate Master Clock
    4. 8.4 Device Functional Modes
      1. 8.4.1 Choosing a Control Mode
        1. 8.4.1.1 Software Control
          1. 8.4.1.1.1 SPI Interface
            1. 8.4.1.1.1.1 Register Read and Write Operation
          2. 8.4.1.1.2 I2C Interface
            1. 8.4.1.1.2.1 Slave Address
            2. 8.4.1.1.2.2 Register Address Auto-Increment Mode
            3. 8.4.1.1.2.3 Packet Protocol
            4. 8.4.1.1.2.4 Write Register
            5. 8.4.1.1.2.5 Read Register
            6. 8.4.1.1.2.6 Timing Characteristics
      2. 8.4.2 VREF and VCOM Modes
    5. 8.5 Programming
  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 Curve
  10. 10Power Supply Recommendations
    1. 10.1 Power Supply Distribution and Requirements
    2. 10.2 Recommended Powerdown Sequence
      1. 10.2.1 XSMT = 0
      2. 10.2.2 Clock Error Detect
      3. 10.2.3 Planned Shutdown
      4. 10.2.4 Unplanned Shutdown
    3. 10.3 External Power Sense Undervoltage Protection Mode
    4. 10.4 Power-On Reset Function
      1. 10.4.1 Power-On Reset, DVDD 3.3-V Supply
      2. 10.4.2 Power-On Reset, DVDD 1.8-V Supply
    5. 10.5 PCM512x Power Modes
      1. 10.5.1 Setting Digital Power Supplies and I/O Voltage Rails
      2. 10.5.2 Power Save Modes
      3. 10.5.3 Power Save Parameter Programming
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Register Maps
    1. 12.1 PCM512x Register Map
      1. 12.1.1 Detailed Register Descriptions
        1. 12.1.1.1 Register Map Summary
        2. 12.1.1.2 Page 0 Registers
        3. 12.1.1.3 Page 1 Registers
        4. 12.1.1.4 Page 44 Registers
        5. 12.1.1.5 Page 253 Registers
      2. 12.1.2 PLL Tables for Software Controlled Devices
      3. 12.1.3 Coefficient Data Formats
      4. 12.1.4 Power Down and Reset Behavior
  13. 13Device and Documentation Support
    1. 13.1 Development Support
    2. 13.2 Documentation Support
    3. 13.3 Related Links
    4. 13.4 Receiving Notification of Documentation Updates
    5. 13.5 Community Resources
    6. 13.6 Trademarks
    7. 13.7 Electrostatic Discharge Caution
    8. 13.8 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

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

8.3.6.1 Clocking Overview

The PCM512x devices have flexible systems for clocking. Internally, the device requires a number of clocks, mostly at related clock rates to function correctly. All of these clocks can be derived from the serial audio interface in one form or another.

PCM5121 PCM5122 f_pcm51xx_clk_bd.gifFigure 62. Audio Flow with Respective Clocks

As shown in Figure 62 the data flows at the sample rate (fS). Once the data is brought into the serial audio interface, it gets processed, interpolated and modulated all the way to 128 × fS before arriving at the current segments for the final digital to analog conversion.

The clock tree is shown in Figure 63.

PCM5121 PCM5122 f_pcm51xx_clk_tree_PLL.gifFigure 63. PCM512x Clock Distribution Tree

The serial audio interface typically has 4 connections: SCK (system master clock), BCK (bit clock), LRCK (left right word clock), and DIN (data). The device has an internal PLL that is used to take either SCK or BCK and create the higher rate clocks required by the interpolating processor and the DAC clock. This allows the device to operate with or without an external SCK.

In situations where the highest audio performance is required, it is suggested that the SCK is brought to the device, along with BCK and LRCK. The device should be configured so that the PLL is only providing a clock source to the audio processing block. By ensuring that the DACCK (DAC Clock) is being driven by the external SCK source, jitter evident in the PLL (in all PLLs) is kept out of the DAC, charge pump, and oversampling system.

Everything else should be a division of the incoming SCK. This is done by setting DAC CLK Source Mux (SDAC in Figure 63) to use SCK as a source, rather than the output of the SCK/PLL Mux. Code examples for this are available in SLASE12.

When the Auto Clock Configuration bit is set (Page 0/ Register 0x25), no additional clocks configuration is required. However, when setting custom PLL values and so forth, the target output rates should match those shown in the recommended PLL values of Table 131.