SBOS959D December   2018  – April 2022 INA819

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Device Comparison Table
  6. Pin Configuration and Functions
  7. Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Typical Characteristics
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Setting the Gain
        1. 8.3.1.1 Gain Drift
      2. 8.3.2 EMI Rejection
      3. 8.3.3 Input Common-Mode Range
      4. 8.3.4 Input Protection
      5. 8.3.5 Operating Voltage
      6. 8.3.6 Error Sources
    4. 8.4 Device Functional Modes
  9. Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Reference Pin
      2. 9.1.2 Input Bias Current Return Path
    2. 9.2 Typical Applications
      1. 9.2.1 Three-Pin Programmable Logic Controller (PLC)
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
        3. 9.2.1.3 Application Curves
      2. 9.2.2 Resistance Temperature Detector Interface
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Development Support
        1. 12.1.1.1 PSpice® for TI
        2. 12.1.1.2 TINA-TI™ Simulation Software (Free Download)
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 Support Resources
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

Setting the Gain

Figure 8-1 shows that the gain of the INA819 is set by a single external resistor (RG) connected between the RG pins (pins 1 and 8).

GUID-C13BCCD8-D7E7-4921-9922-27B5C02AF995-low.gifFigure 8-1 Simplified Diagram of the INA819 With Gain and Output Equations

The value of RG is selected according to Equation 1:

Equation 1. GUID-26D13FE8-B85C-45AB-9060-FF0F7838F712-low.gif

Table 8-1 lists several commonly used gains and resistor values. The 50-kΩ term in Equation 1 is a result of the sum of the two internal 25-kΩ feedback resistors. These on-chip resistors are laser-trimmed to accurate absolute values. The accuracy and temperature coefficients of these resistors are included in the gain accuracy and drift specifications of the INA819. As shown in Figure 8-1 and explained in more details in Section 11, make sure to connect low-ESR, 0.1-µF ceramic bypass capacitors between each supply pin and ground that are placed as close to the device as possible.

Table 8-1 Commonly Used Gains and Resistor Values
DESIRED GAINRG (Ω)NEAREST 1% RG (Ω)
1NCNC
250 k49.9 k
512.5 k12.4 k
105.556 k5.49 k
202.632 k2.61 k
501.02 k1.02 k
100505.1511
200251.3249
500100.2100
100050.0549.9