SBOS562F August 2011  – July 2016 INA826

PRODUCTION DATA. 

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Device Comparison Table
  6. Pin Configuration and Functions
  7. Specifications
    1. 7.1Absolute Maximum Ratings
    2. 7.2ESD Ratings
    3. 7.3Recommended Operating Conditions
    4. 7.4Thermal Information
    5. 7.5Electrical Characteristics
    6. 7.6Typical Characteristics
  8. Detailed Description
    1. 8.1Overview
    2. 8.2Functional Block Diagram
    3. 8.3Feature Description
      1. 8.3.1 Inside the INA826
      2. 8.3.2 Setting the Gain
        1. 8.3.2.1Gain Drift
      3. 8.3.3 Offset Trimming
      4. 8.3.4 Input Common-Mode Range
      5. 8.3.5 Input Protection
      6. 8.3.6 Input Bias Current Return Path
      7. 8.3.7 Reference Terminal
      8. 8.3.8 Dynamic Performance
      9. 8.3.9 Operating Voltage
        1. 8.3.9.1Low-Voltage Operation
      10. 8.3.10Error Sources
    4. 8.4Device Functional Modes
  9. Application and Implementation
    1. 9.1Application Information
    2. 9.2Typical Application
      1. 9.2.1Design Requirements
      2. 9.2.2Detailed Design Procedure
      3. 9.2.3Application Curves
    3. 9.3System Examples
      1. 9.3.1Circuit Breaker
      2. 9.3.2Programmable Logic Controller (PLC) Input
      3. 9.3.3Using TINA-TI SPICE-Based Analog Simulation Program with the INA826
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1Layout Guidelines
      1. 11.1.1CMRR vs Frequency
    2. 11.2Layout Example
  12. 12Device and Documentation Support
    1. 12.1Documentation Support
      1. 12.1.1Related Documentation
    2. 12.2Receiving Notification of Documentation Updates
    3. 12.3Community Resources
    4. 12.4Trademarks
    5. 12.5Electrostatic Discharge Caution
    6. 12.6Glossary
  13. 13Mechanical, Packaging, and Orderable Information

11 Layout

11.1 Layout Guidelines

Attention to good layout practices is always recommended. Keep traces short and, when possible, use a printed circuit board (PCB) ground plane with surface-mount components placed as close to the device pins as possible. Place 0.1-μF bypass capacitors close to the supply pins. Apply these guidelines throughout the analog circuit to improve performance and provide benefits such as reducing the electromagnetic-interference (EMI) susceptibility.

The INA826EVM is intended to provide basic functional evaluation of the INA826. An image of the INA826EVM is provided in Figure 73. The INA826EVM is also available for purchase through the TI eStore.

11.1.1 CMRR vs Frequency

The INA826 pinout is optimized for achieving maximum CMRR performance over a wide range of frequencies. However, care must be taken to ensure that both input paths are well-matched for source impedance and capacitance to avoid converting common-mode signals into differential signals. In addition, parasitic capacitance at the gain-setting pins can also affect CMRR over frequency. For example, in applications that implement gain switching using switches or PhotoMOS® relays to change the value of RG, choose the component so that the switch capacitance is as small as possible.

11.2 Layout Example

INA826 example_layout_sbos562.gif Figure 73. INA826 Example Layout

The INA826EVM provides the following features:

  • Intuitive evaluation with silkscreen schematic
  • Easy access to nodes with surface-mount test points
  • Advanced evaluation with two prototype areas
  • Reference voltage source flexibility
  • Convenient input and output filtering