SBOS566C June   2017  – October 2018 OPA1692

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
    1.     Device Images
      1.      Preamplifier for 3-Wire Electret Microphones
      2.      THD + N vs Frequency (3 VRMS, 2-kΩ Load)
  4. Revision History
  5. Pin Configuration and Functions
    1.     Pin Functions: OPA1692
  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. 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. 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. 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

Battery-Powered Preamplifier for Professional Microphones

Figure 63 shows a preamplifier designed for portable applications that require low-noise, high common-mode rejection, and long battery life. Both channels of the OPA1692 are configured as a two-op amp instrumentation amplifier with a variable gain from 6 to 40 dB. An array of 1-kΩ resistors is recommended for the feedback network because the excellent matching of these resistors ensure high common-mode rejection in the circuit. An OPA171 is configured as a buffered power supply divider to provide a biasing voltage to the circuit, allowing the system to operate properly on a single 9-V battery. The additional components at the OPA1692 inputs are for phantom power, EMI, and ESD protection. The circuit consumes approximately 2 mA of quiescent power supply current.

OPA1692 AI_D003_SBOS566.gifFigure 63. Preamplifier for Professional Microphones Powered from a 9-V Battery