SBOSAA0C november   2021  – may 2023 INA350

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Device Comparison Table
  7. 6 Pin Configuration and Functions
  8. 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
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Gain-Setting
        1. 8.3.1.1 Gain Error and Drift
      2. 8.3.2 Input Common-Mode Voltage Range
      3. 8.3.3 EMI Rejection
      4. 8.3.4 Typical Specifications and Distributions
      5. 8.3.5 Electrical Overstress
    4. 8.4 Device Functional Modes
  10. 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 Resistive-Bridge Pressure Sensor
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
        3. 9.2.1.3 Application Curves
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Development Support
        1. 10.1.1.1 PSpice® for TI
    2. 10.2 Documentation Support
      1. 10.2.1 Related Documentation
    3. 10.3 Receiving Notification of Documentation Updates
    4. 10.4 Support Resources
    5. 10.5 Trademarks
    6. 10.6 Electrostatic Discharge Caution
    7. 10.7 Glossary
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

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

8.3.2 Input Common-Mode Voltage Range

INA350 has two gain stages, the first stage has a common-mode gain of 1 and a differential gain set by the GS pin. The second stage is configured in a difference-amplifier configuration with differential gain of 1 and ideally rejects all of the input common mode completely. The second stage also provides a gain of 1 from REF pin to set the output common-mode voltage.

The linear input voltage range of the INA350, even for a rail-to-rail first stage is dictated by the signal swing at output of the first stage as well as the input common-mode voltage range output swing of the second stage. It is imperative that the INA350 stays linear for a particular combination of gain, reference, and input common-mode voltage for a chosen input differential. Input common-mode voltage (VCM) vs output voltage graphs (VOUT) in this section show a particular reference voltage and gain configuration to outline the linear performance region of INA350. A good common-mode rejection can be expected when operating with in the limits of the VCM vs VOUT graph. Note, that the INA350 linear input voltage cannot be close to or extend beyond the supply rails as the output of the first stage will be driven into saturation.

The common-mode range for the most common operating conditions is outlined as follows. Figure 8-60 shows the region of operation where a minimum of 85 dB can be achieved. Figure 8-61 has much wider region of operation with a lower minimum CMRR of 62 dB, because the input signal crosses over the transition region of the input pairs to achieve rail-to-rail operation. The common-mode range for other operating conditions is best calculated with the INA VCM vs VOUT tool located under the Amplifiers and Comparators section of the Analog Engineer's Calculator on ti.com. INA350-HCM model can be specifically used for applications requiring high CMRR and corresponds to performance shown in Figure 8-60. INA350xxS model can be used for applications where the input common mode can be expected to vary rail-to-rail and it corresponds to performance shown in Figure 8-61 where CMRR drops to 62-dB minimum.

GUID-20211209-SS0I-RXRC-VWX8-FVRLFG1VRGZQ-low.gif
VS = 5.5 V G = 10, 20, 30, 50 VREF = VS / 2
Figure 8-1 Input Common-Mode Voltage vs Output Voltage (High CMRR Region)
GUID-20211209-SS0I-X6ZV-FKVG-J9TVFJ27LG9T-low.gif
VS = 5.5 V G = 10, 20, 30, 50 VREF = VS / 2
Figure 8-2 Input Common-Mode Voltage vs Output Voltage