SLASEM6C October   2017  – October 2020 TAS2770

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
    1.     Pin Functions
  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 I2C Timing Requirements
    7. 6.7 TDM Port Timing Requirements
    8. 6.8 PDM Port Timing Requirements
    9. 6.9 Typical Characteristics
  7. Parameter Measurement Information
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Device Mode and Address Selection
      2. 8.3.2 General I2C Operation
      3. 8.3.3 Single-Byte and Multiple-Byte Transfers
      4. 8.3.4 Single-Byte Write
      5. 8.3.5 Multiple-Byte Write and Incremental Multiple-Byte Write
      6. 8.3.6 Single-Byte Read
      7. 8.3.7 Multiple-Byte Read
      8. 8.3.8 Register Organization
    4. 8.4 Device Functional Modes
      1. 8.4.1  PDM Input
      2. 8.4.2  TDM Port
      3. 8.4.3  Playback Signal Path
        1. 8.4.3.1 High Pass Filter
        2. 8.4.3.2 Digital Volume Control and Amplifier Output Level
        3. 8.4.3.3 Audio Playback Selection
        4. 8.4.3.4 Battery Tracking Limiter with Brown Out Prevention
        5. 8.4.3.5 Inter Chip Limiter Alignment
          1. 8.4.3.5.1 TDM Mode
        6. 8.4.3.6 Class-D Settings
      4. 8.4.4  SAR ADC
      5. 8.4.5  IV Sense
      6. 8.4.6  Clocks and PLL
      7. 8.4.7  Operational Modes
        1. 8.4.7.1 Hardware Shutdown
        2. 8.4.7.2 Software Shutdown
        3. 8.4.7.3 Mute
        4. 8.4.7.4 Active
        5. 8.4.7.5 Mode Control and Software Reset
      8. 8.4.8  Faults and Status
      9. 8.4.9  Power Sequencing Requirements
      10. 8.4.10 Digital Input Pull Downs
    5. 8.5 Register Maps
      1. 8.5.1 Register Summary Table Book=0x00 Page=0x00
      2. 8.5.2 Register Maps
        1. 8.5.2.1  PAGE (book=0x00 page=0x00 address=0x00) [reset=0h]
        2. 8.5.2.2  SW_RESET (book=0x00 page=0x00 address=0x01) [reset=0h]
        3. 8.5.2.3  PWR_CTL (book=0x00 page=0x00 address=0x02) [reset=Eh]
        4. 8.5.2.4  PB_CFG0 (book=0x00 page=0x00 address=0x03) [reset=10h]
        5. 8.5.2.5  PB_CFG1 (book=0x00 page=0x00 address=0x04) [reset=1h]
        6. 8.5.2.6  PB_CFG2 (book=0x00 page=0x00 address=0x05) [reset=0h]
        7. 8.5.2.7  PB_CFG3 (book=0x00 page=0x00 address=0x06) [reset=0h]
        8. 8.5.2.8  MISC_CFG (book=0x00 page=0x00 address=0x07) [reset=6h]
        9. 8.5.2.9  PDM_CFG0 (book=0x00 page=0x00 address=0x08) [reset=0h]
        10. 8.5.2.10 PDM_CFG1 (book=0x00 page=0x00 address=0x09) [reset=8h]
        11. 8.5.2.11 TDM_CFG0 (book=0x00 page=0x00 address=0x0A) [reset=7h]
        12. 8.5.2.12 TDM_CFG1 (book=0x00 page=0x00 address=0x0B) [reset=2h]
        13. 8.5.2.13 TDM_CFG2 (book=0x00 page=0x00 address=0x0C) [reset=Ah]
        14. 8.5.2.14 TDM_CFG3 (book=0x00 page=0x00 address=0x0D) [reset=10h]
        15. 8.5.2.15 TDM_CFG4 (book=0x00 page=0x00 address=0x0E) [reset=13h]
        16. 8.5.2.16 TDM_CFG5 (book=0x00 page=0x00 address=0x0F) [reset=2h]
        17. 8.5.2.17 TDM_CFG6 (book=0x00 page=0x00 address=0x10) [reset=0h]
        18. 8.5.2.18 TDM_CFG7 (book=0x00 page=0x00 address=0x11) [reset=4h]
        19. 8.5.2.19 TDM_CFG8 (book=0x00 page=0x00 address=0x12) [reset=6h]
        20. 8.5.2.20 TDM_CFG9 (book=0x00 page=0x00 address=0x13) [reset=7h]
        21. 8.5.2.21 TDM_CFG10 (book=0x00 page=0x00 address=0x14) [reset=8h]
        22. 8.5.2.22 LIM_CFG0 (book=0x00 page=0x00 address=0x15) [reset=14h]
        23. 8.5.2.23 LIM_CFG1 (book=0x00 page=0x00 address=0x16) [reset=76h]
        24. 8.5.2.24 LIM_CFG2 (book=0x00 page=0x00 address=0x17) [reset=10h]
        25. 8.5.2.25 LIM_CFG3 (book=0x00 page=0x00 address=0x18) [reset=6Eh]
        26. 8.5.2.26 LIM_CFG4 (book=0x00 page=0x00 address=0x19) [reset=1Eh]
        27. 8.5.2.27 LIM_CFG5 (book=0x00 page=0x00 address=0x1A) [reset=58h]
        28. 8.5.2.28 BOP_CFG0 (book=0x00 page=0x00 address=0x1B) [reset=1h]
        29. 8.5.2.29 BOP_CFG1 (book=0x00 page=0x00 address=0x1C) [reset=14h]
        30. 8.5.2.30 BOP_CFG2 (book=0x00 page=0x00 address=0x1D) [reset=4Eh]
        31. 8.5.2.31 ICLA_CFG0 (book=0x00 page=0x00 address=0x1E) [reset=0h]
        32. 8.5.2.32 ICLA_CFG1 (book=0x00 page=0x00 address=0x1F) [reset=0h]
        33. 8.5.2.33 INT_MASK0 (book=0x00 page=0x00 address=0x20) [reset=FCh]
        34. 8.5.2.34 INT_MASK1 (book=0x00 page=0x00 address=0x21) [reset=B1h]
        35. 8.5.2.35 INT_LIVE0 (book=0x00 page=0x00 address=0x22) [reset=0h]
        36. 8.5.2.36 INT_LIVE1 (book=0x00 page=0x00 address=0x23) [reset=0h]
        37. 8.5.2.37 INT_LTCH0 (book=0x00 page=0x00 address=0x24) [reset=0h]
        38. 8.5.2.38 INT_LTCH1 (book=0x00 page=0x00 address=0x25) [reset=0h]
        39. 8.5.2.39 INT_LTCH2 (book=0x00 page=0x00 address=0x26) [reset=0h]
        40. 8.5.2.40 VBAT_MSB (book=0x00 page=0x00 address=0x27) [reset=0h]
        41. 8.5.2.41 VBAT_LSB (book=0x00 page=0x00 address=0x28) [reset=0h]
        42. 8.5.2.42 TEMP_MSB (book=0x00 page=0x00 address=0x29) [reset=0h]
        43. 8.5.2.43 TEMP_LSB (book=0x00 page=0x00 address=0x2A) [reset=0h]
        44. 8.5.2.44 INT_CFG (book=0x00 page=0x00 address=0x30) [reset=5h]
        45. 8.5.2.45 DIN_PD (book=0x00 page=0x00 address=0x31) [reset=0h]
        46. 8.5.2.46 MISC_IRQ (book=0x00 page=0x00 address=0x32) [reset=81h]
        47. 8.5.2.47 CLOCK_CFG (book=0x00 page=0x00 address=0x3C) [reset=Dh]
        48. 8.5.2.48 TDM_DET (book=0x00 page=0x00 address=0x77) [reset=7Fh]
        49. 8.5.2.49 REV_ID (book=0x00 page=0x00 address=0x7D) [reset=20h]
        50. 8.5.2.50 I2C_CKSUM (book=0x00 page=0x00 address=0x7E) [reset=0h]
        51. 8.5.2.51 BOOK (book=0x00 page=0x00 address=0x7F) [reset=0h]
  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
        1. 9.2.2.1 Overview
        2. 9.2.2.2 Select Input Capacitance
        3. 9.2.2.3 Select Decoupling Capacitors
        4. 9.2.2.4 Select Bootstrap Capacitors
      3. 9.2.3 Application Curves
    3. 9.3 Initialization Set Up
      1. 9.3.1 Initial Device Configuration - Auto Rate
      2. 9.3.2 Initial Device Configuration - 48 kHz
      3. 9.3.3 Initial Device Configuration - 44.1 kHz
      4. 9.3.4 Sample Rate Change - 48 kHz to 44.1kHz
      5. 9.3.5 Sample Rate Change - 44.1 kHz to 48 kHz
      6. 9.3.6 Device Mute
      7. 9.3.7 Device Un-Mute
      8. 9.3.8 Device Sleep
      9. 9.3.9 Device Wake
  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 Community Resources
    3. 12.3 Trademarks
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

Battery Tracking Limiter with Brown Out Prevention

The TAS2770 monitors battery voltage (VBAT) and the audio signal to automatically decrease gain when the audio signal peaks exceed a programmable threshold. This helps prevent clipping and extends playback time through end of charge battery conditions. The limiter threshold can be configured to track VBAT below a programmable inflection point with a programmable slope. A minimum threshold sets the limit of threshold reduction from VBAT tracking. Configurable attack rate, hold time and release rate are provided to shape the dynamic response of the limiter (via LIM_ATK_RT[2:0], LIM_HLD_TM[2:0] and LIM_RLS_RT[2:0] register bits).

GUID-E3D27C0A-4C61-42B0-BF38-5572059E4656-low.gifFigure 8-11 Limiter and Brown Out Prevention Interaction Diagram

A Brown Out Prevention (BOP) feature provides a priority input to the limiter to provide very fast response to transient dips in VBAT at end of charge conditions that can cause system level brown out. When VBAT dips below the BOP threshold, the limiter begins reducing gain with an attack latency of less than 10 µs and a configurable attack rate. When VBAT rises above the BOP threshold, the limiter will begin to release after the programmed hold time.

The limiter is enabled by setting the LIM_EN bit register bit high.

Table 8-44 Battery Tracking Limiter Enable
LIM_ENValue
0
Disabled (default)
1
Enabled

The limiter has configurable attack rate, hold time and release rate, which are available via the LIM_ATK_RT[2:0], LIM_HLD_TM[2:0] and LIM_RLS_RT[2:0] register bits respectively. The limiter attack and release step size can be set by configuring the LIM_ATK_ST[1:0] and LIM_RLS_ST[1:0] register bits respectively.

Table 8-45 Limiter Attack Rate
LIM_ATK_RT[2:0]Attack Rate (µs)
0x0
5
0x1
10
0x2
20 (default)
0x3
40
0x4
80
0x5
160
0x6
320
0x7
640
Table 8-46 Limiter Hold Time
LIM_HLD_TM[2:0]Hold Time (ms)
0x0
0
0x1
10
0x2
25
0x3
50
0x4
100
0x5
250
0x6
500 (default)
0x7
1000
Table 8-47 Limiter Release Rate
LIM_RLS_RT[2:0]Release Time (ms)
0x0
10
0x1
50
0x2
100
0x3
250
0x4
500
0x5
750
0x6
1000 (default)
0x7
1500
Table 8-48 Limiter Attack Step Size
LIM_ATK_ST[1:0]Step Size (dB)
00
0.25
01
0.5 (default)
10
1
11
2
Table 8-49 Limiter Release Step Size
LIM_RLS_ST[1:0]Step Size (dB)
00
0.25
01
0.5 (default)
10
1
11
2

A maximum level of attenuation applied by the limiter and brown out prevention feature is configurable via the LIM_MAX_ATN[4:0] register bits. This attenuation limit is shared between the features. For instance, if the maximum attenuation is set to 6 dB and the limiter has reduced gain by 4 dB, the brown out prevention feature will only be able to reduce the gain further by another 2 dB. If the limiter or brown out prevention feature is attacking and it reaches the maximum attenuation, gain will not be reduced any further.

Table 8-50 Limiter Max Attenuation
LIM_MAX_ATN[4:0]Attenuation (dB)
0x00
1
0x01
1.5
...
...
0x10
9 (default)
...
...
0x1E
16
0x1F
16.5

The limiter begins reducing gain when the output signal level is greater than the limiter threshold. The limiter can be configured to track VBAT below a programmable inflection point with a minimum threshold value. Figure 8-12 below shows the limiter configured to limit to a constant level regardless of VBAT level. To achieve this behavior, set the limiter maximum threshold to the desired level via the LIM_TH_MAX[6:0] register bits. Set the limiter inflection point (via the LIM_INF_PT[6:0] register bits) below the minimum allowable VBAT setting. The limiter minimum threshold register bits (LIM_TH_MIN[6:0]) do not impact limiter behavior in this use case.

GUID-41CD361A-8AE2-46F0-99F4-9FC8249BB414-low.gifFigure 8-12 Limiter with Fixed Threshold
Table 8-51 Limiter Maximum Threshold
LIM_TH_MAX[6:0]Threshold (V)
0x00
2
0x01
2.1
...
...
0x6E
13 (default)
...
...
0x7E
14.6
0x7F
14.7
Table 8-52 Limiter Minimum Threshold
LIM_TH_MIN[6:0]Threshold (V)
0x00
2
0x01
2.1
...
...
0x1E
5 (default)
...
...
0x7E
14.6
0x7F
14.7
Table 8-53 Limiter Inflection Point
LIM_INF_PT[6:0]Inflection Point (V)
0x00
2
0x01
2.1
...
...
0x58
10.8 (default)
...
...
0x7E
14.6
0x7F
14.7

Figure 8-13 shows how to configure the limiter to track VBAT below a threshold without a minimum threshold. Set the LIM_TH_MAX[6:0] register bits to the desired threshold and LIM_INF_PT[6:0] register bits to the desired inflection point where the limiter will begin reducing the threshold with VBAT. The LIM_SLOPE[1:0] register bits can be used to change the slope of the limiter tracking with VBAT. The default value of 1 V/V will reduce the threshold 1 V for every 1 V of drop in VBAT. More aggressive tracking slopes can be programmed if desired. Program the LIM_TH_MIN[6:0] below the minimum VBAT to prevent the limiter from having a minimum threshold reduction when tracking VBAT.

GUID-4CFFDE97-D420-47F7-9847-6B31AF0B65E0-low.gifFigure 8-13 Limiter with Inflection Point
Table 8-54 Limiter VBAT Tracking Slope
LIM_SLOPE[1:0]Slope (V/V)
00
1 (default)
01
1.5
10
2
11
4

To achieve a limiter that tracks VBAT below a threshold, configure the limiter as explained in the previous example, except program the LIM_TH_MIN[6:0] register bits to the desired minimum threshold. This is shown in Figure 8-14 below.

GUID-0A42748F-B92E-4024-A863-268EAC2805DC-low.gifFigure 8-14 Limiter with Inflection Point and Minimum Threshold

The TAS2770 also employs a Brown Out Prevention (BOP) feature that serves as a low latency priority input to the limiter engine that begins attacking within 10 µs of VBAT dipping below the programmed BOP threshold. This feature can be enabled by setting the BOP_EN register bit high. It should be noted that the BOP feature is independent of the limiter and will function if enabled even if the limiter is disabled. The BOP threshold is configured by setting the threshold with register bits BOP_TH[7:0].

GUID-521B82F1-0367-4A30-B81D-C236B5698FE7-low.gifFigure 8-15 Limiter Block Diagram
Table 8-55 Brown Out Prevention Enable
BOP_ENValue
0
Disabled
1
Enabled (default)
Table 8-56 Brown Out Prevention Threshold
BOP_TH[7:0]Threshold (V)
0x00
4.5
0x01
4.525
0x02
4.55
...
...
0x14
5.0 (default)
...
...
0xFE
10.85
0xFF
10.875

The BOP feature has a separate attack rate, attack step size and hold time from the battery tracking limiter (register bits BOP_ATK_RT[2:0], BOP_ATK_ST[1:0] and BOP_HLD_TM[2:0] respectively). The BOP feature uses the LIM_RLS_RT[2:0] register setting to release after a brown out event.

Table 8-57 Brown Out Prevention Attack Rate
BOP_ATK_RT[2:0]Attack Rate (µs)
0x0
5
0x1
10
0x2
20 (default)
0x3
40
0x4
80
0x5
160
0x6
320
0x7
640
Table 8-58 Brown Out Prevention Attack Step Size
BOP_ATK_ST[1:0]Step Size (dB)
00
0.5
01
1 (default)
10
1.5
11
2
Table 8-59 Brown Out Prevention Hold Time
BOP_HLD_TM[2:0]Hold Time (ms)
0x0
0
0x1
10
0x2
25
0x3
50
0x4
100
0x5
250
0x6
500 (default)
0x7
1000

The TAS2770 can also shutdown the device when a brown out event occurs if the BOP_SHUTDOWN register bit is set high. For the device to continue playing audio again, the device must transition through a SW/HW shutdown state. Setting the BOP_INF_HLD high will cause the limiter to stay in the hold state (i.e. never release) after a cleared brown out event until either the device transitions through a mute or SW/HW shutdown state or the register bit BOP_HLD_CLR is written to a high value (which will cause the device to exit the hold state and begin releasing). This bit is self clearing and will always readback low. Figure 8-16 below illustrates the entering and exiting from a brown out event.

GUID-C703993D-C57B-47B6-8206-AF38C4D1A1F1-low.gif Figure 8-16 Brown Out Prevention Event
Table 8-60 Shutdown on Brown Out Event
BOP_SHUTDOWNValue
0
Don't Shutdown (default)
1
Shutdown
Table 8-61 Infinite Hold on Brown Out Event
BOP_INF_HLDValue
0
Use BOP_HLD_TM after Brown Out event (default)
1
Do not release until BOP_HLD_CLR is asserted high
Table 8-62 BOP Infinite Hold Clear
BOP_HLD_CLRValue
0
Don't clear (default)
1
Clear event (self clearing)