SBOS075A September   2000  – June 2024 OPA2241 , OPA2251 , OPA241 , OPA251 , OPA4241 , OPA4251

PRODUCTION DATA  

  1.   1
  2. 1Features
  3. 2Applications
  4. 3Description
  5. 4Pin Configuration and Functions
  6. 5Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 Recommended Operating Conditions
    3. 5.3 Thermal Information for OPA241 and OPA251
    4. 5.4 Thermal Information for OPA2241 and OPA2251
    5. 5.5 Thermal Information for OPA4241 and OPA4251
    6. 5.6 Electrical Characteristics for VS = 2.7V to 5V
    7. 5.7 Electrical Characteristics for VS = ±15V
    8. 5.8 Typical Characteristics
  7. 6Application and Implementation
    1. 6.1 Applications Information
      1. 6.1.1 Operating Voltage
      2. 6.1.2 Offset Voltage Trim
      3. 6.1.3 Capacitive Load and Stability
  8. 7Device and Documentation Support
    1. 7.1 Receiving Notification of Documentation Updates
    2. 7.2 Support Resources
    3. 7.3 Trademarks
    4. 7.4 Electrostatic Discharge Caution
    5. 7.5 Glossary
  9. 8Revision History
  10. 9Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

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

Capacitive Load and Stability

The OPAx241 series and OPAx251 series can drive a wide range of capacitive loads. However, all op amps under certain conditions can be unstable. Op amp configuration, gain, and load value are just a few of the factors to consider when determining stability.

Figure 6-2 and Figure 6-3 show the regions where the OPAx241 series and OPAx251 series have the potential for instability. As shown, the unity gain configuration with low supplies is the most susceptible to the effects of capacitive load. With VS = 5V, G = 1, and IOUT = 0, operation remains stable with load capacitance up to approximately 200pF. Increasing a combination of supply voltage, output current, and gain significantly improves capacitive load drive. For example, increasing the supplies to ±15V and gain to 10 drives approximately 2700pF.

Figure 6-4 shows one method to improve capacitive load drive in the unity gain configuration by inserting a resistor inside the feedback loop. This reduces ringing with large capacitive loads while maintaining dc accuracy. For example, with VS = ±1.35V and RS = 5kΩ, the OPAx241 series and OPAx251 series perform well with capacitive loads in excess of 1000pF. Without the series resistor, the capacitive load drive is typically 200pF for these conditions. However, this method results in a slight reduction of output voltage swing.

OPA241 OPA2241 OPA4241 OPA251 OPA2251 OPA4251 Stability—Capacitive Load vs Output Current
                    for Low Supply Voltage Figure 6-2 Stability—Capacitive Load vs Output Current for Low Supply Voltage
OPA241 OPA2241 OPA4241 OPA251 OPA2251 OPA4251 Stability—Capacitive Load vs Output Current
                    for ±15V Supplies Figure 6-3 Stability—Capacitive Load vs Output Current for ±15V Supplies
OPA241 OPA2241 OPA4241 OPA251 OPA2251 OPA4251 Series Resistor in Unity Gain
                    Configuration Improves Capacitive Load Drive Figure 6-4 Series Resistor in Unity Gain Configuration Improves Capacitive Load Drive
OPA241 OPA2241 OPA4241 OPA251 OPA2251 OPA4251 Low-Side and High-Side Battery Current
                    Sensing Figure 6-5 Low-Side and High-Side Battery Current Sensing