ZHCSIQ4B September   2018  – December 2018 OPA828

PRODUCTION DATA.  

  1. 特性
  2. 应用
  3. 说明
    1.     Device Images
      1.      开环增益和相位与频率间的关系
      2.      失调电压漂移
  4. 修订历史记录
  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 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Operating Characteristics
      2. 7.3.2  Phase-Reversal Protection
      3. 7.3.3  Electrical Overstress
      4. 7.3.4  MUX Friendly Inputs
      5. 7.3.5  Overload Power Limiter
      6. 7.3.6  Capacitive Load and Stability
      7. 7.3.7  Capacitive Load and Stability
      8. 7.3.8  Settling Time
      9. 7.3.9  Slew Rate
      10. 7.3.10 Full Power Bandwidth
      11. 7.3.11 Small Signal Response
      12. 7.3.12 Thermal Considerations
      13. 7.3.13 Thermal Shutdown
      14. 7.3.14 Low Noise
      15. 7.3.15 Low Offset Voltage Drift
      16. 7.3.16 Overload Recovery
    4. 7.4 Device Functional Modes
      1. 7.4.1 Functional Modes
  8. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Typical Application: SAR ADC Driver
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Typical Application: Low-Pass Filter
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
        3. 8.2.2.3 Application Curve
  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
    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 术语表
  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

Capacitive Load and Stability

Figure 48 shows the total circuit noise for varying source impedances with the operational amplifier in a unity-gain configuration (with no feedback resistor network and therefore no additional noise contributions). The OPA828 and OPA211 are shown with total circuit noise calculated. The op amp itself contributes both a voltage noise component and a current noise component. The voltage noise is commonly modeled as a time-varying component of the offset voltage. The current noise is modeled as the time-varying component of the input bias current and reacts with the source resistance to create a voltage component of noise. Therefore, the lowest noise op amp for a given application depends on the source impedance. For low source impedance, current noise is negligible, and voltage noise generally dominates. The OPA828 device has both low voltage noise and extremely low current noise because of the FET input of the op amp. As a result, the current noise contribution of the OPA828 is negligible for any practical source impedance, which makes it the better choice for applications with high source impedance.

The equation in shows the calculation of the total circuit noise, with these parameters:

  • en = voltage noise
  • In = current noise
  • RS = source impedance
  • k = Boltzmann's constant = 1.38 × 10–23 J/K
  • T = temperature in degrees Kelvin (K)
OPA828 Noise Performance Comparison.gifFigure 48. Noise Performance of the OPA828 and OPA211 in Unity-Gain Buffer Configuration