SBOS859B March   2018  – July 2018 INA1620

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      INA1620 Simplified Internal Schematic
      2.      FFT: 1 kHz, 32-Ω Load, 50 mW
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin 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
    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 Matched Thin-Film Resistor Pairs
      2. 7.3.2 Power Dissipation
      3. 7.3.3 Thermal Shutdown
      4. 7.3.4 EN Pin
      5. 7.3.5 GND Pin
      6. 7.3.6 Input Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 Shutdown Mode
      2. 7.4.2 Output Transients During Power Up and Power Down
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Noise Performance
      2. 8.1.2 Resistor Tolerance
      3. 8.1.3 EMI Rejection
      4. 8.1.4 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 Preamplifier for Professional Microphones
  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 (Free Software Download)
        2. 11.1.1.2 TI Precision Designs
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Community Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

7.3.1 Matched Thin-Film Resistor Pairs

The INA1620 integrates four thin-film resistor pairs. Each pair is made up of two thin-film resistors with a nominal resistance of 1 kΩ. While the absolute value of the resistor is not trimmed and can vary significantly, the two resistors in an pair are designed to match each other extremely well. The resistors in an pair typically match to within 0.004% of each other's value. This matching is also preserved well over temperature, with the matching drift having a 0.2 ppm/°C maximum specification. Each node in the resistor pair is bonded out to a pad on the INA1620 package allowing the resistor pairs to be used in multiple configurations. The nodes in the pair are protected from damage due to electrostatic discharge (ESD) events by diodes tied to the power supplies of the IC. For this reason, voltages beyond the power supplies cannot be applied to the resistors without forward-biasing the ESD protection diodes. The resistor pairs should not be used if there is no power applied to the INA1620. The configuration of the ESD protection diodes is shown in Figure 44.

INA1620 ai_D100.gifFigure 44. ESD Protection Diodes on Each Resistor Pair

Although the resistor pairs and amplifier core are fabricated on the same silicon substrate, they can be used in separate circuits as long as the previously-mentioned voltage limits are observed. The functional state of the amplifier (enabled or shutdown) does not affect the resistor pair's performance.