SNAS856 September   2024 REF80

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 Thermal Information
    4. 6.4 Recommended Operating Conditions
    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 Heater
      2. 7.3.2 Buried Zener Reference
  9. 8 Parameter Measurement Information
    1. 8.1 Long-Term Stability
    2. 8.2 Temperature Drift
    3. 8.3 Noise Performance
      1. 8.3.1 1/f Noise
      2. 8.3.2 Broadband Noise
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 Typical Application: Basic Voltage Reference Connection
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Application Curve
      2. 9.2.2 Typical Application Circuits
        1. 9.2.2.1 Precision Voltage Divider Connection
        2. 9.2.2.2 Calibration Signal
    3. 9.3 Power Supply Recommendation
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
  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

8.3.1 1/f Noise

1/f noise, also known as flicker noise, is dominant mostly in the lower frequency bands. Flicker noise affects the device output voltage which can affect the ENOB of the signal chain. REF80 data sheet specifies flicker noise for 0.1Hz to 10Hz frequency band where 1/f noise has maximum power. Flicker noise is measured by filtering the output from 0.1Hz to 10Hz. Since the 1/f noise is an extremely low value, the frequency of interest needs to be amplified and band-pass filtered as shown in Figure 8-4. 1/f noise must be tested in a Faraday cage enclosure to block environmental noise. Refer to application note Techniques for Noise Measurements in Precision Series References for more detail on noise measurement for precision series references.

REF80 1/f Noise Test Setup Figure 8-4 1/f Noise Test Setup

Typical 1/f noise (0.1Hz to 10Hz) distribution can be seen in Figure 8-5.

REF80 0.1Hz to 10Hz Voltage Noise Distribution Figure 8-5 0.1Hz to 10Hz Voltage Noise Distribution

The 1/f noise is in such a low frequency range that it is not practical to filter out which makes it a key parameter for ultra-low noise measurements. Noise sensitive designs must use the lowest 1/f noise for the highest precision measurements. Figure 8-6 shows the effect of 1/f noise over 10s.

REF80 0.1Hz to 10Hz Voltage Noise Figure 8-6 0.1Hz to 10Hz Voltage Noise