ZHCSGP3D September   2017  – December 2018 OPA2837 , OPA837

PRODUCTION DATA.  

  1. 特性
  2. 应用
    1.     具有真正接地输入和输出范围的低功耗、低噪声、精密单端 SAR ADC 驱动器
  3. 说明
    1.     Device Images
  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: OPA837
    5. 6.5  Thermal Information: OPA2837
    6. 6.6  Electrical Characteristics: VS = 5 V
    7. 6.7  Electrical Characteristics: VS = 3 V
    8. 6.8  Typical Characteristics: VS = 5.0 V
    9. 6.9  Typical Characteristics: VS = 3.0 V
    10. 6.10 Typical Characteristics: ±2.5-V to ±1.5-V Split Supply
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagrams
    3. 7.3 Feature Description
      1. 7.3.1 OPA837 Comparison
      2. 7.3.2 Input Common-Mode Voltage Range
      3. 7.3.3 Output Voltage Range
      4. 7.3.4 Power-Down Operation
      5. 7.3.5 Low-Power Applications and the Effects of Resistor Values on Bandwidth
      6. 7.3.6 Driving Capacitive Loads
    4. 7.4 Device Functional Modes
      1. 7.4.1 Split-Supply Operation (±1.35 V to ±2.7 V)
      2. 7.4.2 Single-Supply Operation (2.7 V to 5.4 V)
  8. Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1  Noninverting Amplifier
      2. 8.1.2  Inverting Amplifier
      3. 8.1.3  Output DC Error Calculations
      4. 8.1.4  Output Noise Calculations
      5. 8.1.5  Instrumentation Amplifier
      6. 8.1.6  Attenuators
      7. 8.1.7  Differential to Single-Ended Amplifier
      8. 8.1.8  Differential-to-Differential Amplifier
      9. 8.1.9  Pulse Application With Single-Supply Circuit
      10. 8.1.10 ADC Driver Performance
    2. 8.2 Typical Applications
      1. 8.2.1 Active Filters
        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 Implementing a 2:1 Active Multiplexer
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
      3. 8.2.3 1-Bit PGA Operation
        1. 8.2.3.1 Design Requirements
        2. 8.2.3.2 Detailed Design Procedure
  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 文档支持
      1. 11.1.1 相关文档
    2. 11.2 相关链接
    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

Output DC Error Calculations

The OPAx837 can provide excellent DC signal accuracy because of its high open-loop gain, high common-mode rejection, high power-supply rejection, and low input offset voltage and bias current offset errors. To take full advantage of this low input offset voltage, pay careful attention to input bias current cancellation. The low-noise input stage for the OPAx837 has a relatively high input bias current (0.34 µA typical out the pins) but with a close match between the two input currents. The OPAx837 is a negative rail input device using PNP input devices where the base current flows out of the device pins. A large resistor to ground on the V+ input shifts the pin voltage positively because of the input bias current. The mismatch between the two input bias currents is very low, typically only ±10 nA of input offset current. Match the DC source impedances out of the two inputs to reduce the total output offset voltage. Figure 67 illustrates an example of resistor matching for bias current cancellation. Analyzing the simple circuit of Figure 67 (using a gain of 2-V/V target with RF = RG = 2 kΩ) illustrates that the noise gain for the input offset voltage drift is 1 + 2 kΩ / 2 kΩ = 2 V/V. This value results in an output drift term of ±1.6 µV/°C × 2 = ±3.2 µV/°C (DCK package). Because the two impedances out of the inputs are matched, the residual error from the maximum ±250 pA/°C offset current drift is this maximum IOS drift times the 2-kΩ feedback resistor value, or ±50 µV/°C. The total output DC error drift band is ±53.2 µV/°C. If the output DC drift is more important than reduced feedback currents, lower the resistor values to reduce the dominant drift term resulting from the IOS term.