SNVSCN7A November   2023  – December 2023 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

9.2.1.2 Detailed Design Procedure

A bulk capacitor (0.1 μF to 10 μF) must be connected to the supply to improve transient response in the applications where the supply voltage can fluctuate. Connect an additional 0.1 μF capacitor at VIN pin closer to the device to bypass high frequency supply noise.

A low ESR (maximum 1 Ω) capacitor of 1 μF to 100 μF must be connected to the output to provide stable output. For very low noise applications, special care must be taken with X7R and other MLCC capacitors due to their piezoelectric effect. Piezoelectric property of multilayer ceramic capacitors (MLCC) can introduce a μV range noise due to mechanical vibrations, potentially dominating the noise of the REF54. More information on how the piezoelectric effect can be explored in systems can be found in Stress-induced outbursts: Microphonics in ceramic capacitors (Part 1) and Stress-induced outbursts: Microphonics in ceramic capacitors (Part 2). Designer must use film capacitors for noise sensitive applications. TI recommends placing the REF54 reference as close to the load as possible to minimize IR drop due to trace resistance.

The transient startup response of the REF54 is shown in Figure 9-7. The startup response of the REF54 family is dependent on the output and NR pin capacitor. Increasing the output capacitor improves the load transient performance of the device, however this also increases the startup time. Figure 9-3 shows the startup time with CNR = 10 μF, increases to 3 seconds.