SLASE64A December   2014  – June 2017 PCM1860-Q1 , PCM1861-Q1 , PCM1862-Q1 , PCM1863-Q1 , PCM1864-Q1 , PCM1865-Q1

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Device Comparison Table
  6. Pin Configuration and Functions
  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: PGA and ADC AC Performance
    6. 7.6  Electrical Characteristics: DC
    7. 7.7  Electrical Characteristics: Digital Filter
    8. 7.8  Timing Requirements: External Clock
    9. 7.9  Timing Requirements: I2C Control Interface
    10. 7.10 Timing Requirements: SPI Control Interface
    11. 7.11 Timing Requirements: Audio Data Interface for Slave Mode
    12. 7.12 Timing Requirements: Audio Data Interface for Master Mode
    13. 7.13 Typical Characteristics
  8. Parameter Measurement Information
  9. Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagrams
    3. 9.3 Features Description
      1. 9.3.1  Analog Front End
      2. 9.3.2  Microphone Support
        1. 9.3.2.1 Mic Bias
      3. 9.3.3  Input Multiplexer (PCM1860-Q1 and PCM1861-Q1)
      4. 9.3.4  Mixers and Multiplexers (PCM1862-Q1, PCM1863-Q1, PCM1864-Q1, and PCM1865-Q1)
      5. 9.3.5  Programmable Gain Amplifier
      6. 9.3.6  Automatic Clipping Suppression
        1. 9.3.6.1 Attenuation Level
        2. 9.3.6.2 Channel Linking
      7. 9.3.7  Zero Crossing Detect
      8. 9.3.8  Digital Inputs
        1. 9.3.8.1 Stereo PCM Sources
        2. 9.3.8.2 Digital PDM Microphones
      9. 9.3.9  Clocks
        1. 9.3.9.1 Description
        2. 9.3.9.2 External Clock-Source Limits
        3. 9.3.9.3 Device Clock Distribution and Generation
        4. 9.3.9.4 Clocking Modes
          1. 9.3.9.4.1 Clock Configuration and Selection for Hardware-Controlled Devices
          2. 9.3.9.4.2 Clock Sources for Software-Controlled Devices
          3. 9.3.9.4.3 Clocking Configuration and Selection for Software-Controlled Devices
            1. 9.3.9.4.3.1 Target Clock Rates for ADC, DSP1 and DSP2
            2. 9.3.9.4.3.2 Configuration of Master Mode
          4. 9.3.9.4.4 BCK Input Slave PLL Mode
          5. 9.3.9.4.5 Software-Controlled Devices ADC Non-Audio MCK PLL Mode
        5. 9.3.9.5 Software-Controlled Devices Manual PLL Calculation
        6. 9.3.9.6 Clock Halt and Error
        7. 9.3.9.7 Clock Halt and Error Detect
        8. 9.3.9.8 Changes in Clock Sources and Sample Rates
      10. 9.3.10 Analog-to-Digital Converters (ADCs)
        1. 9.3.10.1 Main Audio ADCs
        2. 9.3.10.2 Secondary ADC: Energysense and Analog Control
          1. 9.3.10.2.1 Secondary ADC Analog Input Range
          2. 9.3.10.2.2 Frequency Response of the Secondary ADC
        3. 9.3.10.3 Secondary ADC Controlsense DC Level Change Detection
      11. 9.3.11 Energysense
        1. 9.3.11.1 Energysense Signal Loss Flag
        2. 9.3.11.2 Energysense Signal Detect Circuitry
          1. 9.3.11.2.1 Energysense Threshold Levels for Both Signal Loss and Signal Detect
        3. 9.3.11.3 Programming Various Coefficients for Energysense
      12. 9.3.12 Audio Processing
        1. 9.3.12.1 DSP1 Processing Features
          1. 9.3.12.1.1 Digital Decimation Filters
          2. 9.3.12.1.2 Digital PGA
        2. 9.3.12.2 DSP2 Processing Features
          1. 9.3.12.2.1 Digital Mixing Function
      13. 9.3.13 Fade-In and Fade-Out Functions
      14. 9.3.14 Mappable GPIO Pins
      15. 9.3.15 Interrupt Controller
        1. 9.3.15.1 DIN Toggle Detection
        2. 9.3.15.2 Clearing Interrupts
          1. 9.3.15.2.1 Reset Energysense Loss (in Active Mode)
          2. 9.3.15.2.2 Reset Energysense Detect (In Sleep Mode)
          3. 9.3.15.2.3 Reset Controlsense (Active and Sleep Modes)
          4. 9.3.15.2.4 Reset DIN Toggle (In Sleep Mode)
          5. 9.3.15.2.5 Reset PGA Clipping (Active)
      16. 9.3.16 Audio Format Selection and Timing Details
        1. 9.3.16.1 Audio Format Selection
        2. 9.3.16.2 Serial Audio Interface Timing Details
        3. 9.3.16.3 Digital Audio Output 2 Configuration
        4. 9.3.16.4 Time Division Multiplex (TDM Support)
        5. 9.3.16.5 Decimation Filter Select
        6. 9.3.16.6 Serial Audio Data Interface Configuration
    4. 9.4 Device Functional Modes
      1. 9.4.1 Power Mode Descriptions
        1. 9.4.1.1 PCM1860-Q1 and PCM1861-Q1 Hardware Device Power Down Functions
          1. 9.4.1.1.1 Enter Standby Mode (From Active Mode)
          2. 9.4.1.1.2 Exit From Standby Mode Back to Active
          3. 9.4.1.1.3 Enter or Exit Sleep or Energysense Mode to Active
        2. 9.4.1.2 PCM186x-Q1 Software Device Power Down Functions
          1. 9.4.1.2.1 Enter or Exit Stand-by Mode
          2. 9.4.1.2.2 Enter Sleep Mode
          3. 9.4.1.2.3 Exit Sleep Mode
        3. 9.4.1.3 Bypassing the Internal LDO to Reduce Power Consumption
    5. 9.5 Programming
      1. 9.5.1 Control
        1. 9.5.1.1 Hardware Control Configuration
        2. 9.5.1.2 Software-Controlled Device Configuration
        3. 9.5.1.3 SPI Interface
          1. 9.5.1.3.1 Register Read and Write Operation
        4. 9.5.1.4 I2C Interface
          1. 9.5.1.4.1 Slave Address
          2. 9.5.1.4.2 Packet Protocol
      2. 9.5.2 Current Status Registers
      3. 9.5.3 Real World Software Configuration using Energysense and Controlsense
        1. 9.5.3.1 Active Mode Flow Diagram
        2. 9.5.3.2 Basic Device Configuration
        3. 9.5.3.3 Clear Energysense Interrupt
        4. 9.5.3.4 Update System Settings
        5. 9.5.3.5 Sleep Mode Flow Diagram
        6. 9.5.3.6 Update Controlsense values in Sleep Mode
          1. 9.5.3.6.1 Update System Settings
      4. 9.5.4 Programming and Register Reference
        1. 9.5.4.1 Coefficient Data Formats
      5. 9.5.5 Programming DSP Coefficients on Software-Controlled Devices
  10. 10Application and Implementation
    1. 10.1 Application Information
      1. 10.1.1 Device Control Method
        1. 10.1.1.1 Hardware Control
        2. 10.1.1.2 Software Control
          1. 10.1.1.2.1 SPI Control
          2. 10.1.1.2.2 I2C Control
      2. 10.1.2 Power-Supply Options
        1. 10.1.2.1 3.3-V AVDD, DVDD, and IOVDD
        2. 10.1.2.2 3.3-V AVDD, DVDD, and 1.8-V IOVDD
      3. 10.1.3 Master Clock Source
      4. 10.1.4 Dual PCM186x-Q1 TDM Functionality
      5. 10.1.5 Analog Input Configuration
        1. 10.1.5.1 Analog Front-End Circuit For Single-Ended, Line-In Applications
        2. 10.1.5.2 Analog Front-End Circuit for Differential, Line-In Applications
    2. 10.2 Typical Applications
      1. 10.2.1 Stereo Recording Application for PCM186x-Q1 Hardware-Controlled Devices in Master Mode
        1. 10.2.1.1 Design Requirements
        2. 10.2.1.2 Detailed Design Procedure
        3. 10.2.1.3 Application Curves
      2. 10.2.2 Stereo Recording Application for PCM186x-Q1 Software-Controlled Devices in Slave PLL Mode with 1.8-V IOVDD
        1. 10.2.2.1 Design Requirements
        2. 10.2.2.2 Detailed Design Procedure
        3. 10.2.2.3 Application Curves
  11. 11Power Supply Recommendations
    1. 11.1 Power-Supply Distribution and Requirements
    2. 11.2 1.8-V Support
    3. 11.3 Brownout Conditions
    4. 11.4 Power-Up Sequence
    5. 11.5 Lowest Power-Down Modes
      1. 11.5.1 Lowest Power In Standby Mode (AVDD = DVDD = IOVDD = 3.3 V)
      2. 11.5.2 Lowest Power in Sleep or Energysense Mode (AVDD = DVDD = IOVDD = 3.3 V)
      3. 11.5.3 Lower Power in Sleep or Energysense Mode (AVDD = DVDD 3.3 V and IOVDD = 1.8 V)
    6. 11.6 Power-On Reset Sequencing Timing Diagram
    7. 11.7 Power Connection Examples
      1. 11.7.1 3.3-V AVDD, DVDD, and IOVDD Example
      2. 11.7.2 3.3-V AVDD, DVDD With 1.8-V IOVDD Example for Lower-Power Applications
    8. 11.8 Fade In
  12. 12Layout
    1. 12.1 Layout Guidelines
      1. 12.1.1 Grounding and System Partitioning
    2. 12.2 Layout Example
  13. 13Register Map
    1. 13.1 Register Map Description
    2. 13.2 Register Map Summary
    3. 13.3 Page 0 Registers
      1. 13.3.1  Page 0: Register 1 (address = 0x01) [reset = 0x00]
      2. 13.3.2  Page 0: Register 2 (address = 0x02) [reset = 0x00]
      3. 13.3.3  Page 0: Register 3 (address = 0x03) [reset = 0x00]
      4. 13.3.4  Page 0: Register 4 (address = 0x04) [reset = 0x00]
      5. 13.3.5  Page 0: Register 5 (address = 0x05) [reset = 0x86]
      6. 13.3.6  Page 0: Register 6 (address = 0x06) [reset = 0x41]
      7. 13.3.7  Page 0: Register 7 (address = 0x07) [reset = 0x41]
      8. 13.3.8  Page 0: Register 8 (address = 0x08) [reset = 0x42]
      9. 13.3.9  Page 0: Register 9 (address = 0x09) [reset = 0x42]
      10. 13.3.10 Page 0: Register 10 (address = 0x0A) [reset = 0x00]
      11. 13.3.11 Page 0: Register 11 (address = 0x0B) [reset = 0x44]
      12. 13.3.12 Page 0: Register 12 (address = 0x0C) [reset = 0x00]
      13. 13.3.13 Page 0: Register 13 (address = 0x0D) [reset = 0x00]
      14. 13.3.14 Page 0: Register 14 (address = 0x0E) [reset = 0x00]
      15. 13.3.15 Page 0: Register 15 (address = 0x0F) [reset = 0x00]
      16. 13.3.16 Page 0: Register 16 (address = 0x10) [reset = 0x01]
      17. 13.3.17 Page 0: Register 17 (address = 0x11) [reset = 0x20]
      18. 13.3.18 Page 0: Register 18 (address = 0x12) [reset = 0x00]
      19. 13.3.19 Page 0: Register 19 (address = 0x13) [reset = 0x00]
      20. 13.3.20 Page 0: Register 20 (address = 0x14) [reset = 0x00]
      21. 13.3.21 Page 0: Register 21 (address = 0x15) [reset = 0x00]
      22. 13.3.22 Page 0: Register 22 (address = 0x16) [reset = 0x00]
      23. 13.3.23 Page 0: Register 23 (address = 0x17) [reset = 0x00]
      24. 13.3.24 Page 0: Register 24 (address = 0x18) [reset = 0x00]
      25. 13.3.25 Page 0: Register 25 (address = 0x19) [reset = 0x00]
      26. 13.3.26 Page 0: Register 26 (address = 0x1A) [reset = 0x00]
      27. 13.3.27 Page 0: Register 27 (address = 0x1B) [reset = 0x00]
      28. 13.3.28 Page 0: Register 32 (address = 0x20) [reset = 0x01]
      29. 13.3.29 Page 0: Register 33 (address = 0x21) [reset = 0x00]
      30. 13.3.30 Page 0: Register 34 (address = 0x22) [reset = 0x01]
      31. 13.3.31 Page 0: Register 35 (address = 0x23) [reset = 0x03]
      32. 13.3.32 Page 0: Register 37 (address = 0x25) [reset = 0x07]
      33. 13.3.33 Page 0: Register 38 (address = 0x26) [reset = 0x03]
      34. 13.3.34 Page 0: Register 39 (address = 0x27) [reset = 0x3F]
      35. 13.3.35 Page 0: Register 40 (address = 0x28) [reset = 0x01]
      36. 13.3.36 Page 0: Register 41 (address = 0x29) [reset = 0x00]
      37. 13.3.37 Page 0: Register 42 (address = 0x2A) [reset = 0x00]
      38. 13.3.38 Page 0: Register 43 (address = 0x2B) [reset = 0x01]
      39. 13.3.39 Page 0: Register 44 (address = 0x2C) [reset = 0x00]
      40. 13.3.40 Page 0: Register 45 (address = 0x2D) [reset = 0x00]
      41. 13.3.41 Page 0: Register 48 (address = 0x30) [reset = 0x00]
      42. 13.3.42 Page 0: Register 49 (address = 0x31) [reset = 0x00]
      43. 13.3.43 Page 0: Register 50 (address = 0x32) [reset = 0x00]
      44. 13.3.44 Page 0: Register 51 (address = 0x33) [reset = 0x00]
      45. 13.3.45 Page 0: Register 52 (address = 0x34) [reset = 0x00]
      46. 13.3.46 Page 0: Register 54 (address = 0x36) [reset = 0x01]
      47. 13.3.47 Page 0: Register 64 (address = 0x40) [reset =0x80]
      48. 13.3.48 Page 0: Register 65 (address = 0x41) [reset = 0x7F]
      49. 13.3.49 Page 0: Register 66 (address = 0x42) [reset = 0x00]
      50. 13.3.50 Page 0: Register 67 (address = 0x43) [reset = 0x80]
      51. 13.3.51 Page 0: Register 68 (address = 0x44) [reset = 0x7F]
      52. 13.3.52 Page 0: Register 69 (address = 0x45) [reset = 0x00]
      53. 13.3.53 Page 0: Register 70 (address = 0x46) [reset = 0x80]
      54. 13.3.54 Page 0: Register 71 (address = 0x47) [reset = 0x7F]
      55. 13.3.55 Page 0: Register 72 (address = 0x48) [reset = 0x00]
      56. 13.3.56 Page 0: Register 73 (address = 0x49) [reset = 0x80]
      57. 13.3.57 Page 0: Register 74 (address = 0x4A) [reset = 0x7F]
      58. 13.3.58 Page 0: Register 75 (address = 0x4B) [reset = 0x00]
      59. 13.3.59 Page 0: Register 76 (address = 0x4C) [reset = 0x80]
      60. 13.3.60 Page 0: Register 77 (address = 0x4D) [reset = 0x7F]
      61. 13.3.61 Page 0: Register 78 (address = 0x4E) [reset = 0x00]
      62. 13.3.62 Page 0: Register 79 (address = 0x4F) [reset = 0x80]
      63. 13.3.63 Page 0: Register 80 (address = 0x50) [reset = 0x7F]
      64. 13.3.64 Page 0: Register 81 (address = 0x51) [reset = 0x00]
      65. 13.3.65 Page 0: Register 82 (address = 0x52) [reset = 0x80]
      66. 13.3.66 Page 0: Register 83 (address = 0x53) [reset = 0x7F]
      67. 13.3.67 Page 0: Register 84 (address = 0x54) [reset = 0x00]
      68. 13.3.68 Page 0: Register 85 (address = 0x55) [reset = 0x80]
      69. 13.3.69 Page 0: Register 86 (address = 0x56) [reset = 0x7F]
      70. 13.3.70 Page 0: Register 87 (address = 0x57) [reset = 0x00]
      71. 13.3.71 Page 0: Register 88 (address = 0x58) [reset = 0x00]
      72. 13.3.72 Page 0: Register 89 (address = 0x59) [reset = 0x00]
      73. 13.3.73 Page 0: Register 90 (address = 0x5A) [reset = 0x00]
      74. 13.3.74 Page 0: Register 96 (address = 0x60) [reset = 0x01]
      75. 13.3.75 Page 0: Register 97 (address = 0x61) [reset = 0x00]
      76. 13.3.76 Page 0: Register 98 (address = 0x62) [reset =0x10]
      77. 13.3.77 Page 0: Register 112 (address = 0x70) [reset = 0x70]
      78. 13.3.78 Page 0: Register 113 (address = 0x71) [reset = 0x10]
      79. 13.3.79 Page 0: Register 114 (address = 0x72) [reset = 0x00]
      80. 13.3.80 Page 0: Register 115 (address = 0x73) [reset = 0x00]
      81. 13.3.81 Page 0: Register 116 (address = 0x74) [reset = 0x00]
      82. 13.3.82 Page 0: Register 117 (address = 0x75) [reset = 0x00]
      83. 13.3.83 Page 0: Register 120 (address = 0x78) [reset = 0x00]
    4. 13.4 Page 1 Registers
      1. 13.4.1  Page 1: Register 1 (address = 0x01) [reset = 0x00]
      2. 13.4.2  Page 1: Register 2 (address = 0x02) [reset = 0x00]
      3. 13.4.3  Page 1: Register 4 (address = 0x04) [reset = 0x00]
      4. 13.4.4  Page 1: Register 5 (address = 0x05) [reset = 0x00]
      5. 13.4.5  Page 1: Register 6 (address = 0x06) [reset = 0x00]
      6. 13.4.6  Page 1: Register 7 (address = 0x07) [reset = 0x00]
      7. 13.4.7  Page 1: Register 8 (address = 0x08) [reset = 0x00]
      8. 13.4.8  Page 1: Register 9 (address = 0x09) [reset = 0x00]
      9. 13.4.9  Page 1: Register 10 (address = 0x0A) [reset = 0x00]
      10. 13.4.10 Page 1: Register 11 (address = 0x0B) [reset = 0x00]
    5. 13.5 Page 3 Registers
      1. 13.5.1 Page 3: Register 18 (address = 0x12) [reset =0x40]
      2. 13.5.2 Page 3: Register 21 (address = 0x15) [reset = 0x01]
    6. 13.6 Page 253 Registers
      1. 13.6.1 Page 253: Register 20 (address = 0x14) [reset = 0x00]
  14. 14Device and Documentation Support
    1. 14.1 Development Support
    2. 14.2 Related Links
    3. 14.3 Receiving Notification of Documentation Updates
    4. 14.4 Community Resources
    5. 14.5 Trademarks
    6. 14.6 Electrostatic Discharge Caution
    7. 14.7 Glossary
  15. 15Mechanical, Packaging, and Orderable Information

Power Supply Recommendations

Power-Supply Distribution and Requirements

The PCM186x-Q1 powers the device using the pins shown in Figure 68.

PCM1860-Q1 PCM1861-Q1 PCM1862-Q1 PCM1863-Q1 PCM1864-Q1 PCM1865-Q1 pcm186x-power-tree.gif Figure 68. PCM186x-Q1 Power Distribution Tree

The PCM186x-Q1 uses a combination of 3.3-V functional blocks and 1.8-V functional blocks to achieve high analog performance, combined with high levels of digital integration. As such, the device has three internal power rails. AVDD provides the analog circuits with a clean 3.3-V rail. DVDD is used for 3.3-V digital clock circuits. Externally, AVDD and DVDD can be connected together without significant impact to performance. The final rail, IOVDD, is used for driving the input/output digital circuitry.

The PCM186x-Q1 integrates an on-chip LDO to convert an external 3.3 V to the 1.8 V required by the digital core. The LDO input is derived from IOVDD. Power-supply pin descriptions are listed in Table 24.

Table 24. Power-Supply Pin Descriptions

NAME DESCRIPTION
AVDD Analog voltage supply (3.3 V) that powers the ADC, PGA, reference, and secondary ADC.
DVDD Digital voltage supply (3.3 V) that is used for the PLL and the oscillator circuit.
IOVDD Input/output pin voltage. Also used as a source for the internal LDO for the digital circuit.
LDO Output from the on-chip LDO that is used with a 0.1-µF decoupling capacitor. Can be driven (used as power input) with a 1.8-V supply to bypass the on-chip LDO for lower power consumption.
AGND Analog ground
DGND Digital ground

1.8-V Support

All PCM186x-Q1 devices can support external devices with a 1.8 V I/O. This operating mode is configured by driving IOVDD and LDO with 1.8 V.

Brownout Conditions

The PCM186x-Q1 devices do not have a brownout detector, or a reset pin to hold while the system is powering up. Make sure that the system design meets minimum AVDD, DVDD and IOVDD requirements.

Power-Up Sequence

The power-up sequence consists of the following steps:

  1. Power-on reset
    1. Power up AVDD, DVDD and IOVDD
    2. Check if LDO is being driven with an external 1.8 V, or is an output. Enable LDO if required.
    3. Release digital reset
  2. Wait until analog voltage reference is stable
  3. Configure clock (PLL requires < 250 µs)
  4. Fade-in audio ADC content

Lowest Power-Down Modes

To achieve the lowest levels of power down and sleep current, the following recommended write sequences are suggested on PCM186x-Q1 software-controlled devices:

Lowest Power In Standby Mode (AVDD = DVDD = IOVDD = 3.3 V)

Consumption as low as 0.59 mW

0x00=0x00 //select page0 0x70=0x14 //power down reference 0x00=0x03 //select page3 0x12=0x41 //disable OSC 0x00=0x00 //select page0

Lowest Power in Sleep or Energysense Mode (AVDD = DVDD = IOVDD = 3.3 V)

Consumption as low as 14 mW

Clocks must be running during this process

0x00=0x00 //select page0

0x70=0x72 //enter in sleep mode

0x00=0xfd //select page253

0x14=0x10 //change global bias current

0x00=0x00 //select page0

Now stop the clocks

Lower Power in Sleep or Energysense Mode (AVDD = DVDD 3.3 V and IOVDD = 1.8 V)

Consumption as low as 11.15 mW

Clocks must be running during this process

0x00=0x00 //select page0

0x70=0x72 //enter in sleep mode

0x00=0xfd //select page253

0x14=0x10 //change global bias current

0x00=0x00 //select page0

stop the clocks (note: make sure the clock IO is 1.8 V)

Power-On Reset Sequencing Timing Diagram

PCM1860-Q1 PCM1861-Q1 PCM1862-Q1 PCM1863-Q1 PCM1864-Q1 PCM1865-Q1 pcm186x_pwr_up-down.gif Figure 69. Power-On Reset Timing Diagram

Power Connection Examples

3.3-V AVDD, DVDD, and IOVDD Example

This example shows the most typical usage. One single supply, shared between all three supply voltage inputs. Rail-connected decoupling capacitors are not shown. Figure 70 shows 3.3-V supply for all supplies. Figure 71 shows separate 3.3 V for AVDD and DVDD.

NOTE

There is no disadvantage in separating the AVDD and DVDD, as the device waits until both are present before powering up.

PCM1860-Q1 PCM1861-Q1 PCM1862-Q1 PCM1863-Q1 PCM1864-Q1 PCM1865-Q1 pcm186x_typ_pwr3v3.gif Figure 70. 3.3 V for All Supplies
PCM1860-Q1 PCM1861-Q1 PCM1862-Q1 PCM1863-Q1 PCM1864-Q1 PCM1865-Q1 pcm186x_pwr_separate_a_dvdd.gif Figure 71. Separate 3.3 V for AVDD and DVDD

3.3-V AVDD, DVDD With 1.8-V IOVDD Example for Lower-Power Applications

The PCM186x-Q1 also supports interfacing to lower power 1.8-V processors, as shown in Figure 72. In the presence of an external 1.8 V connected to LDO, the internal LDO that takes DVDD (3.3 V) and converts it to the 1.8-V core voltage is bypassed. Under such conditions, IOVDD will then be used as the 1.8-V source for the digital core of the device. In such systems, it is still important to have 3.3 V for DVDD, as specific sections of the digital core in the device run from 3.3 V.

PCM1860-Q1 PCM1861-Q1 PCM1862-Q1 PCM1863-Q1 PCM1864-Q1 PCM1865-Q1 pcm186x_pwr_separate_iovdd.gif Figure 72. 1.8-V IOVDD With 3.3 V for AVDD and DVDD

Fade In

This sequence is the final stage of the power up and is illustrated in Figure 73. After the PLL has locked, the ADC starts running, and the data follows the fade-in sequence according to the following steps:

  1. Detect a zero crossing audio input.
  2. Increment the volume towards 0 dB with S-shaped volume.
  3. Repeat from step 1 until the result is 0 dB. The number of steps from mute to 0 dB is 48 steps.
  4. If zero crossing does not occur for 8192 sample times (= time out), change the volume-per-sample time.

PCM1860-Q1 PCM1861-Q1 PCM1862-Q1 PCM1863-Q1 PCM1864-Q1 PCM1865-Q1 pcm186x_zerocrossingfadein.gif Figure 73. S-Curve Fade-In Behavior