ZHCSH28B September   2017  – December 2017 TPA3221

PRODUCTION DATA.  

  1. 特性
  2. 应用
  3. 说明
    1.     简化原理图
  4. 修订历史记录
  5. Device Comparison Table
  6. Pin Configuration and Functions
    1.     Pin 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
    6. 7.6 Audio Characteristics (BTL)
    7. 7.7 Audio Characteristics (PBTL)
    8. 7.8 Typical Characteristics, BTL Configuration, AD-mode
    9. 7.9 Typical Characteristics, PBTL Configuration, AD-mode
  8. Parameter Measurement Information
  9. Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagrams
    3. 9.3 Feature Description
      1. 9.3.1 Internal LDO
        1. 9.3.1.1 Input Configuration, Gain Setting And Master / Slave Operation
      2. 9.3.2 Gain Setting And Master / Slave Operation
      3. 9.3.3 AD-Mode and HEAD-Mode PWM Modulation
      4. 9.3.4 Oscillator
      5. 9.3.5 Input Impedance
      6. 9.3.6 Error Reporting
    4. 9.4 Device Functional Modes
      1. 9.4.1 Powering Up
        1. 9.4.1.1 Startup Ramp Time
      2. 9.4.2 Powering Down
        1. 9.4.2.1 Power Down Ramp Time
      3. 9.4.3 Device Reset
      4. 9.4.4 Device Soft Mute
      5. 9.4.5 Device Protection System
        1. 9.4.5.1 Overload and Short Circuit Current Protection
        2. 9.4.5.2 Signal Clipping and Pulse Injector
        3. 9.4.5.3 DC Speaker Protection
        4. 9.4.5.4 Pin-to-Pin Short Circuit Protection (PPSC)
        5. 9.4.5.5 Overtemperature Protection OTW and OTE
        6. 9.4.5.6 Undervoltage Protection (UVP), Overvoltage Protection (OVP) and Power-on Reset (POR)
        7. 9.4.5.7 Fault Handling
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Applications
      1. 10.2.1 Stereo BTL Application
        1. 10.2.1.1 Design Requirements
        2. 10.2.1.2 Detailed Design Procedures
          1. 10.2.1.2.1 Decoupling Capacitor Recommendations
          2. 10.2.1.2.2 PVDD Capacitor Recommendation
          3. 10.2.1.2.3 BST capacitors
          4. 10.2.1.2.4 PCB Material Recommendation
      2. 10.2.2 Typical Application, Differential (2N), AD-Mode PBTL (Outputs Paralleled before LC filter)
        1. 10.2.2.1 Design Requirements
      3. 10.2.3 Typical Application, Differential (2N), AD-Mode PBTL (Outputs Paralleled after LC filter)
        1. 10.2.3.1 Design Requirements
  11. 11Power Supply Recommendations
    1. 11.1 Power Supplies
      1. 11.1.1 VDD Supply
      2. 11.1.2 AVDD and GVDD Supplies
      3. 11.1.3 PVDD Supply
      4. 11.1.4 BST Supply
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Examples
      1. 12.2.1 BTL Application Printed Circuit Board Layout Example
      2. 12.2.2 PBTL (Outputs Paralleled before LC filter) Application Printed Circuit Board Layout Example
      3. 12.2.3 PBTL (Outputs Paralleled after LC filter) Application Printed Circuit Board Layout Example
  13. 13器件和文档支持
    1. 13.1 文档支持
    2. 13.2 接收文档更新通知
    3. 13.3 社区资源
    4. 13.4 商标
    5. 13.5 静电放电警告
    6. 13.6 Glossary
  14. 14机械、封装和可订购信息

封装选项

机械数据 (封装 | 引脚)
散热焊盘机械数据 (封装 | 引脚)
订购信息

Input Impedance

The TPA3221 input stage is a fully differential input stage and the input impedance changes with the gain setting from 7.7 kΩ at 34 dB gain to 47 kΩ at 18 dB gain. Table 1 lists the values from min to max gain. The tolerance of the input resistor value is ±20 % so the minimum value will be higher than 6.2 kΩ. The inputs need to be AC-coupled to minimize the output DC-offset and ensure correct ramping of the output voltages during power-ON and power-OFF. The input ac-coupling capacitor together with the input impedance forms a high-pass filter with the following cut-off frequency:

If a flat bass response is required down to 20 Hz the recommended cut-off frequency is a tenth of that, 2 Hz. Table 3 lists the recommended ac-couplings capacitors for each gain step. If a -3 dB is accepted at 20 Hz 10 times lower capacitors can used – for example, a 1 μF can be used.

Table 3. Recommended Input AC-Coupling Capacitors

Gain Input Impedance Input AC-Coupling Capacitance Input High Pass Filter
18 dB 48 kΩ 4.7 µF 0.7 Hz
24 dB 24 kΩ 10 µF 0.7 Hz
30 dB 12 kΩ 10 µF 1.3 Hz
34 dB 7.7 kΩ 10 µF 2.1 Hz

The input capacitors used should be a type with low leakage, like quality electrolytic, tantalum, film or ceramic. If a polarized type is used the positive connection should face such that the capacitor has a positive DC bias.