ZHCSJ01B January   2019  – August 2019 OPA1671

PRODUCTION DATA.  

  1. 1 特性
  2. 2 应用
  3. 3 说明
    1.     Device Images
      1.      驻极体麦克风前置放大器
      2.      OPA1671 电压噪声密度
  4. 4 修订历史记录
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 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 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Operating Voltage
      2. 7.3.2 Input Bias Current
      3. 7.3.3 Common-Mode Voltage Range
      4. 7.3.4 EMI Susceptibility and Input Filtering
    4. 7.4 Device Functional Modes
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Capacitive Loads
      2. 8.1.2 Noise Performance
      3. 8.1.3 Basic Noise Calculations
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11器件和文档支持
    1. 11.1 器件支持
      1. 11.1.1 开发支持
        1. 11.1.1.1 TINA-TI（免费软件下载）
    2. 11.2 文档支持
      1. 11.2.1 相关文档
    3. 11.3 接收文档更新通知
    4. 11.4 社区资源
    5. 11.5 商标
    6. 11.6 静电放电警告
    7. 11.7 Glossary
  12. 12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

8.2.2 Detailed Design Procedure

The preamplifier circuit uses a noninverting gain configuration to allow for high input impedance, with independent gain-setting resistor values. DC bypass is accomplished with C2 and C3, with the low frequency poles set by C2, R4, C3 and R5; see Equation 1 and Equation 2.

Equation 1. OPA1671 opa1671_equation1.gif
Equation 2. OPA1671 opa1671_equation2.gif

The filter cutoff frequency is determined by a higher frequency pole, set by R5 and C4.

Equation 3. OPA1671 opa1671_equation5.gif

The gain of the circuit in the passband is set by R5 and R6.

Equation 4. OPA1671 opa1671_equation3.gif

The ouput noise of the circuit (ignoring the electret microphone intrinsic noise and impedance) is the RSS average noise contribution from R5 and the input voltage noise of OPA1671. R5 was selected for minimal noise contribution without requiring a dc blocking cap. (C3) larger than 10 µF. See Equation 5 for the output noise density calculation at 10 kHz.

Equation 5. OPA1671 opa1671_equation4.gif