SBOS516H September   2010  – June 2024 OPA171 , OPA2171 , OPA4171

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Pin Configuration and Functions
  6. Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information: OPA171
    5. 5.5 Thermal Information: OPA2171
    6. 5.6 Thermal Information: OPA4171
    7. 5.7 Electrical Characteristics
    8. 5.8 Typical Characteristics: Table of Graphs
    9. 5.9 Typical Characteristics
  7. Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Operating Characteristics
      2. 6.3.2 Common-Mode Voltage Range
      3. 6.3.3 Phase-Reversal Protection
      4. 6.3.4 Capacitive Load and Stability
    4. 6.4 Device Functional Modes
      1. 6.4.1 Common-Mode Voltage Range
  8. Application and Implementation
    1. 7.1 Application Information
      1. 7.1.1 Electrical Overstress
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
        1. 7.2.2.1 Capacitive Load and Stability
      3. 7.2.3 Application Curve
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
  9. Device and Documentation Support
    1. 8.1 Support Resources
    2. 8.2 Support Resources
    3. 8.3 Trademarks
    4. 8.4 Electrostatic Discharge Caution
    5. 8.5 Glossary
  10. Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Capacitive Load and Stability

The dynamic characteristics of the OPAx171-Q1 family of devices have been optimized for commonly encountered operating conditions. The combination of low closed-loop gain and high capacitive loads decreases the phase margin of the amplifier and can lead to gain peaking or oscillations. As a result, heavier capacitive loads must be isolated from the output. The simplest way to achieve this isolation is to add a small resistor (for example, ROUT equal to 50 Ω) in series with the output. Figure 6-2 and Figure 6-3 show small-signal overshoot versus capacitive load for several values of ROUT. For details of analysis techniques and application circuits, see Applications Bulletin AB-028, available for download from TI.com.

OPA171 OPA2171 OPA4171 Small-Signal Overshoot vs Capacitive Load (100-mV Output Step)Figure 6-2 Small-Signal Overshoot vs Capacitive Load (100-mV Output Step)
OPA171 OPA2171 OPA4171 Small-Signal Overshoot vs Capacitive Load (100-mV Output Step)Figure 6-3 Small-Signal Overshoot vs Capacitive Load (100-mV Output Step)