SBVS058D June   2005  – April 2026 REF3212 , REF3220 , REF3225 , REF3230 , REF3233 , REF3240

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Electrical Characteristics
    4. 5.4 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
      1. 6.1.1 Supply Voltage
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Thermal Hysteresis
      2. 6.3.2 Temperature Drift
      3. 6.3.3 Noise Performance
      4. 6.3.4 Load Regulation
    4. 6.4 Device Functional Modes
      1. 6.4.1 Shutdown
  8. 7 Application and Implementation
    1. 7.1 Application Information
      1. 7.1.1 Long-Term Stability
    2. 7.2 Typical Application
      1. 7.2.1 Detailed Design Procedure
        1. 7.2.1.1 Negative Reference Voltage
        2. 7.2.1.2 Data Acquisition
  9. 8 Device and Documentation Support
    1. 8.1 Receiving Notification of Documentation Updates
    2. 8.2 Support Resources
    3. 8.3 Trademarks
    4. 8.4 Electrostatic Discharge Caution
    5. 8.5 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

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

6.1 Overview

The REF32xx is a family of CMOS, precision band-gap voltage references. Figure 6-1 shows the basic band-gap topology. Transistors Q1 and Q2 are biased so that the current density of Q1 is greater than that of Q2. The difference of the two base-emitter voltages (Vbe1 – Vbe2) has a positive temperature coefficient and is forced across resistor R1. This voltage is amplified and added to the base-emitter voltage of Q2, which has a negative temperature coefficient. The resulting output voltage is virtually independent of temperature.

REF3212 REF3220 REF3225 REF3230 REF3233 REF3240 Simplified Schematic of Band-gap ReferenceFigure 6-1 Simplified Schematic of Band-gap Reference