SNVSCN7B November   2023  – June 2024 REF54

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 REF54250
    6. 6.6  Electrical Characteristics REF54300
    7. 6.7  Electrical Characteristics REF54410
    8. 6.8  Electrical Characteristics REF54450
    9. 6.9  Electrical Characteristics REF54500
    10. 6.10 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
      2. 8.3.2 NR Pin
  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 Reference Attach With High Precision ADC
    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

Package Options

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

7.3.1 1/f Noise

1/f noise, also known as flicker noise, is dominant mostly in the lower frequency bands. REF54 data sheet specifies flicker noise for 0.1 Hz to 10 Hz frequency band where 1/f noise has maximum power. Since the 1/f noise is an extremely low value, the frequency of interest is amplified and filtered through a precise band filter with very low noise floor as shown in Figure 7-3.

REF54 1/f Noise Test Setup Figure 7-3 1/f Noise Test Setup

Figure 7-4 shows typical distribution of flicker noise for multiple devices where more than 1000 samples have been captured for each device.

REF54 0.1-Hz to 10-Hz Voltage Noise Distribution (CNR = Open)Figure 7-4 0.1-Hz to 10-Hz Voltage Noise Distribution (CNR = Open)

Noise sensitive designs prefer the lowest 1/f noise for the highest precision measurements. REF54 offers NR pin which creates a low pass filters on the band gap with typical resistance of 13 kΩ. 100 μF capacitor on NR pin removes the whole band of flicker noise (0.1 Hz) from the band gap reference as shown in Figure 7-5. A 10 μF capacitor on the NR pin creates a 1 Hz low-pass filter for the bandgap.

REF54 0.1-Hz to 10-Hz Voltage Noise (CNR = 100 μF)Figure 7-5 0.1-Hz to 10-Hz Voltage Noise
(CNR = 100 μF)
REF54 0.1-Hz to 10-Hz Voltage Noise (CNR = 10 μF)Figure 7-6 0.1-Hz to 10-Hz Voltage Noise
(CNR = 10 μF)