SBOS549C April   2011  – March 2021 OPA2376-Q1 , OPA376-Q1 , OPA4376-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and 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: OPA376-Q1
    5. 6.5 Thermal Information: OPA2376-Q1
    6. 6.6 Thermal Information: OPA4376-Q1
    7. 6.7 Electrical Characteristics
    8. 6.8 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 Offset Voltage and Input Offset Voltage Drift
      3. 7.3.3 Capacitive Load and Stability
      4. 7.3.4 Common-Mode Voltage Range
      5. 7.3.5 Input and ESD Protection
    4. 7.4 Device Functional Modes
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Basic Amplifier Configurations
      2. 8.1.2 Active Filtering
      3. 8.1.3 Driving an Analog-to-Digital Converter
      4. 8.1.4 Phantom-Powered Microphone
      5. 8.1.5 Speech Bandpass-Filtered Data Acquisition System
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curve
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Development Support
        1. 11.1.1.1 TINA-TI™ Simulation Software (Free Download)
        2. 11.1.1.2 TI Precision Designs
        3. 11.1.1.3 WEBENCH® Filter Designer
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Support Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

8.1.4 Phantom-Powered Microphone

The circuit shown in Figure 8-4 depicts how a remote microphone amplifier can be powered by a phantom source on the output side of the signal cable. The cable serves double duty, carrying both the differential output signal from and dc power to the microphone amplifier stage.

An OPA2376-Q1 serves as a single-ended input to a differential output amplifier with a 6-dB gain. Common-mode bias for the two op amps is provided by the dc voltage developed across the electret microphone element. A 48-V phantom supply is reduced to 5.1 V by the series 6.8-kΩ resistors on the output side of the cable, and the 4.7-kΩ resistors and zener diode on the input side of the cable. AC coupling blocks the different dc voltage levels from each other on each end of the cable.

An INA163 instrumentation amplifier provides differential inputs and receives the balanced audio signals from the cable.

The INA163 gain may be set from 0 dB to 80 dB by selecting the RG value. The INA163 circuit is typical of the input circuitry used in mixing consoles.

GUID-CA1A0AF0-785D-42C5-BD2B-2582EDF2F5C2-low.gifFigure 8-4 Phantom-Powered Electret Microphone