SBOS925A December   2020  – January 2021 OPA391

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  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
    6. 6.6 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Low Input Bias Current
      2. 7.3.2 Input Differential Voltage
      3. 7.3.3 Capacitive Load Drive
      4. 7.3.4 EMI Rejection
    4. 7.4 Device Functional Modes
  8. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Three-Terminal CO Gas Sensor
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curve
      2. 8.2.2 4-mA to 20-mA Loop Design
        1. 8.2.2.1 Application Curve
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Development Support
        1. 11.1.1.1 TINA-TI™ Simulation Software (Free Download)
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Support Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

Description

The OPA391 features a unique combination of high bandwidth (1 MHz) along with very low quiescent current (24 µA) in a high-precision amplifier. These features combined with rail-to-rail input and output make this device an exceptional choice in high-gain, low-power applications. Ultra-low input bias current of 10 fA, only 45 µV of offset (maximum), and 1.2 µV/°C of drift over temperature help maintain high precision in ratiometric and amperometric sensor front ends that have demanding low-power requirements.

The OPA391 uses Texas Instrument's proprietary e‑trim™ operational amplifier technology, enabling a unique combination of ultra-low offset and low input offset drift without the need for any input switching or auto-zero techniques. The CMOS-based technology platform also features a modern, robust output stage design that is tolerant of high output capacitance, alleviating stability problems that are common in typical low-power amplifiers.

Device Information
PART NUMBERPACKAGE(1)BODY SIZE (NOM)
OPA391SC-70 (5)2.00 mm x 1.25 mm
For all available packages, see the package option addendum at the end of the data sheet.
GUID-20201113-CA0I-K6ZQ-LNKJ-VVKRCCCJ3D0J-low.gifHigh Input Impedance, Low Offset Buffer
GUID-20201116-CA0I-DBDQ-SBRP-GBHMJDNPZZ0G-low.gifOPA391 Offset Voltage