SBAS798 September   2017 REF2125

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
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  7. 7 Parameter Measurement Information
    1. 7.1 Solder Heat Shift
    2. 7.2 Long-Term Stability
    3. 7.3 Thermal Hysteresis
    4. 7.4 Power Dissipation
    5. 7.5 Noise Performance
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Supply Voltage
      2. 8.3.2 Low Temperature Drift
      3. 8.3.3 Load Current
      4. 8.3.4 Clean Start Feature
    4. 8.4 Device Functional Modes
      1. 8.4.1 EN Pin
      2. 8.4.2 Negative Reference Voltage
  9. 9 Applications and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application: Basic Voltage Reference Connection
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Input and Output Capacitors
        2. 9.2.2.2 VIN Slew Rate Considerations
        3. 9.2.2.3 Shutdown/Enable Feature
      3. 9.2.3 Application Curves
  10. 10Power-Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 Receiving Notification of Documentation Updates
    3. 12.3 Community Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

11 Layout

11.1 Layout Guidelines

Figure 31 illustrates an example of a PCB layout for a data acquisition system using the REF2125. Some key considerations are:

  • Connect low-ESR, 0.1-μF ceramic bypass capacitors at VIN, VREF of the REF2125.
  • Decouple other active devices in the system per the device specifications.
  • Using a solid ground plane helps distribute heat and reduces electromagnetic interference (EMI) noise pickup.
  • Place the external components as close to the device as possible. This configuration prevents parasitic errors (such as the Seebeck effect) from occurring.
  • Do not run sensitive analog traces in parallel with digital traces. Avoid crossing digital and analog traces if possible, and only make perpendicular crossings when absolutely necessary.

11.2 Layout Example

REF2125 layout_SBAS798.gif Figure 31. Layout Example