SBVS299A April   2017  – September 2025 REF31-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
  7. 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
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Supply Voltage
      2. 7.3.2 Thermal Hysteresis
      3. 7.3.3 Temperature Drift
      4. 7.3.4 Noise Performance
      5. 7.3.5 Long-Term Stability
      6. 7.3.6 Load Regulation
    4. 7.4 Device Functional Modes
      1. 7.4.1 Negative Reference Voltage
      2. 7.4.2 Data Acquisition
  9. 8 Application and Implementation
    1. 8.1 Application Information
    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 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

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

7.3.1 Supply Voltage

The REF31xx-Q1 family of references features an extremely low dropout voltage. With the exception of the REF3112, which has a minimum supply requirement of 1.8 V, these references can be operated with a supply of only 5 mV above the output voltage in an unloaded condition. For loaded conditions, a typical dropout voltage versus load is shown in Typical Characteristics.

The REF31xx-Q1 features a low quiescent current that is extremely stable over changes in both temperature and supply. The typical room temperature quiescent current is 100 μA, and the maximum quiescent current over temperature is just 135 μA. The quiescent current typically changes less than 2 μA over the entire supply range, as shown in Figure 7-1.

REF31-Q1 Supply Current vs Supply VoltageFigure 7-1 Supply Current vs Supply Voltage

Supply voltages below the specified levels can cause the REF31xx-Q1 to momentarily draw currents greater than the typical quiescent current. This can be prevented by using a power supply with a fast rising edge and low output impedance.