SNVSCU8 August   2026 REF53-Q1

ADVANCE INFORMATION  

  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 REF53-Q1
    6. 6.6 Typical Characteristics
  8. 7 Parameter Measurement Information
    1. 7.1 Temperature Drift
    2. 7.2 Long-Term Stability
    3. 7.3 Noise Performance
      1. 7.3.1 1/f Noise
      2. 7.3.2 Broadband Noise
    4. 7.4 Thermal Hysteresis
    5. 7.5 Solder Heat Shift
    6. 7.6 Power Dissipation
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 EN Pin
    4. 8.4 Device Functional Modes
      1. 8.4.1 Basic Connections
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 Basic Voltage Reference Connection
        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 Constant Current Reference
    3. 9.3 Power Supply Recommendation
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Documentation Support
      1. 10.1.1 Related Documentation
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information
    1. 12.1 Tape and Reel Information
    2. 12.2 Mechanical Data

9.2.2 Constant Current Reference

Multiple applications such as sensor biasing, LED driving, battery charging, and so forth need, precision constant current source. REF53-Q1 device with precision performance, wide input voltage support, multiple output voltage options meets various application level requirements to be configured as constant current source.

Figure 9-4 shows REF53-Q1 configured as a constant current source. REF53-Q1 is configured as floating device with device GND driving the load. The precision voltage reference from REF53-Q1 along with an external precision reference draw a constant current from the input supply denoted as 'I'. The effective current flowing through the load is combination of REF53-Q1 device quiescent current and the programmed value I. The wide VIN voltage support of REF53-Q1 allows for wide voltage variation across the load while still maintaining the constant current accuracy.

REF53-Q1 REF53-Q1 Configuration as Constant Current Source Figure 9-4 REF53-Q1 Configuration as Constant Current Source

Table 9-2 shows the measured results as per the design shown in Figure 9-4.

Table 9-2 Constant Current Source Results
VREF R CALCULATED CURRENT MEASURED CURRENT
1.25V 1.4kΩ 0.978mA 0.998mA
1.25V 127Ω 9.93mA 9.98mA
1.25V 62Ω 20.24mA 20.33mA