SBAS901C July   2018  – October 2020 REF34-Q1

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Device Comparison Table
  6. Pin Configuration and Functions
    1. 6.1 Pin Functions
  7. Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
  8. Typical Characteristics
  9. Parameter Measurement Information
    1. 9.1 Solder Heat Shift
    2. 9.2 Long-Term Stability
    3. 9.3 Thermal Hysteresis
    4. 9.4 Power Dissipation
    5. 9.5 Noise Performance
  10. 10Detailed Description
    1. 10.1 Overview
    2. 10.2 Functional Block Diagram
    3. 10.3 Feature Description
      1. 10.3.1 Supply Voltage
      2. 10.3.2 Low Temperature Drift
      3. 10.3.3 Load Current
    4. 10.4 Device Functional Modes
      1. 10.4.1 EN Pin
  11. 11Application and Implementation
    1. 11.1 Application Information
    2. 11.2 Typical Applications
      1. 11.2.1 Basic Voltage Reference Connection
        1. 11.2.1.1 Design Requirements
        2. 11.2.1.2 Detailed Design Procedure
          1. 11.2.1.2.1 Input and Output Capacitors
          2. 11.2.1.2.2 4-Wire Kelvin Connections
          3. 11.2.1.2.3 VIN Slew Rate Considerations
          4. 11.2.1.2.4 Shutdown/Enable Feature
        3. 11.2.1.3 Application Curves
      2. 11.2.2 Advanced Driver Assistance Systems (ADAS) Microcontroller Connection
        1. 11.2.2.1 Basic Voltage Reference Connection
        2. 11.2.2.2 Design Requirements
        3. 11.2.2.3 Detailed Design Procedure
        4. 11.2.2.4 Enable Feature in ADAS
  12. 12Power Supply Recommendations
  13. 13Layout
    1. 13.1 Layout Guidelines
    2. 13.2 Layout Example
  14. 14Device and Documentation Support
    1. 14.1 Documentation Support
      1. 14.1.1 Related Documentation
    2. 14.2 Receiving Notification of Documentation Updates
    3. 14.3 Support Resources
    4. 14.4 Trademarks
    5. 14.5 Electrostatic Discharge Caution
    6. 14.6 Glossary
  15. 15Mechanical, Packaging, and Orderable Information

Package Options

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

Design Requirements

In ADAS applications it is common to use an ADC with a MCU to monitor the voltage rails to the MCU/DSP/FPGAs. In figure Figure 11-4 the automotive TI Jacinto™ TDA2 MCU is using a ADS7828-Q1 to monitor several analog input signals and in ADAS these signals will be the system power rails. It is important to monitor these power rails because tighter rail requirements allow for further system monitoring and optimization. The REF3425-Q1 is used in this application to provide the precise voltage reference signal. In these systems it is not typical to have calibration and such the most precise low power voltage reference is necessary to be able to measure down to 1% accuracy on key power rails.

For this design example, use the parameters listed in Table 11-3 as the input parameters and desired output parameters.

Table 11-3 Typical Core Voltage Rail Monitoring
SPECIFICATION REQUIREMENT
Input Voltage VIN 3V
Output Voltage 2.5V
Voltage Power Rail 1V
Max Error on Voltage Power Rail 1%
Temperature Range -40°C to 125°C