SBOSAI7B November   2023  – July 2024 OPA2891 , OPA891

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 Recommended Operating Conditions
    4. 5.4 Thermal Information - OPA891
    5. 5.5 Thermal Information - OPA2891
    6. 5.6 Electrical Characteristics - RL = 150Ω
    7. 5.7 Electrical Characteristics - RL = 1kΩ
    8. 5.8 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagrams
    3. 6.3 Feature Description
      1. 6.3.1 Offset Nulling
    4. 6.4 Device Functional Modes
  8. 7 Application and Implementation
    1. 7.1 Application Information
      1. 7.1.1 Driving a Capacitive Load
      2. 7.1.2 Low-Pass Filter Configurations
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
        1. 7.2.2.1 Selection of Multiplexer
        2. 7.2.2.2 Signal Source
        3. 7.2.2.3 Driving Amplifier
        4. 7.2.2.4 Driving Amplifier Bandwidth Restriction
      3. 7.2.3 Application Curves
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
        1. 7.4.1.1 General PowerPAD™ Integrated Circuit Package Design Considerations
      2. 7.4.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 Documentation Support
      1. 8.1.1 Related Documentation
    2. 8.2 Receiving Notification of Documentation Updates
    3. 8.3 Support Resources
    4. 8.4 Trademarks
    5. 8.5 Electrostatic Discharge Caution
    6. 8.6 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • D|8
  • DGN|8
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7.2.2.3 Driving Amplifier

The driving operational amplifier (OPA3 in Figure 7-4) in this application must have good slew rate, bandwidth, low noise, and distortion. The input of the operational amplifier can result in a maximum step of 4V because of MUX switching. As a result, even if the signal bandwidth is low, the driving amplifier must settle from a 4V step within one ADC sampling frame to avoid signal distortion. In this example, the settling requirement due to the ADC selection is 500ns. The OPA891 is a good choice in this application due to the high slew rate and low distortion of this operational amplifier.