SBOS566C June   2017  – October 2018 OPA1692

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Preamplifier for 3-Wire Electret Microphones
      2.      THD + N vs Frequency (3 VRMS, 2-kΩ Load)
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions: OPA1692
  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: OPA1692
    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 Distortion Reduction
      2. 7.3.2 Phase Reversal Protection
      3. 7.3.3 Electrical Overstress
    4. 7.4 Device Functional Modes
      1. 7.4.1 Operating Voltage
  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
      4. 8.1.4 EMI Rejection
      5. 8.1.5 EMIRR +IN Test Configuration
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curves
    3. 8.3 Other Application Examples
      1. 8.3.1 Two-Wire Electret Microphone Preamplifier
      2. 8.3.2 Battery-Powered Preamplifier for Professional Microphones
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Power Dissipation
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Development Support
        1. 11.1.1.1 TINA-TI™ (Free Software Download)
        2. 11.1.1.2 DIP Adapter EVM
        3. 11.1.1.3 Universal Operational Amplifier EVM
        4. 11.1.1.4 Smart Amplifier Speaker Characterization Board Evaluation Module
        5. 11.1.1.5 TI Precision Designs
        6. 11.1.1.6 WEBENCH Filter Designer
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Related Links
    4. 11.4 Receiving Notification of Documentation Updates
    5. 11.5 Community Resource
    6. 11.6 Trademarks
    7. 11.7 Electrostatic Discharge Caution
    8. 11.8 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

8.1.2 Noise Performance

Figure 56 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 op amp itself contributes 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 OPA169x has low voltage noise and low current noise. As a result, the current noise contribution of the OPA169x series is negligible for source impedances less than 100 kΩ.

Figure 56 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)

For more details on calculating noise, see Basic Noise Calculations.

OPA1692 C004_SBOS566.pngFigure 56. Noise Performance of the OPA169x in a Unity-Gain Buffer Configuration