SBOSA95D May   2022  – December 2023 OPA2863A , OPA863A

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Device Comparison Table
  6. Pin Configuration and Functions
  7. Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  Recommended Operating Conditions
    4. 6.4  Thermal Information: OPA863A
    5. 6.5  Thermal Information: OPA2863A
    6. 6.6  Electrical Characteristics: VS = ±5 V
    7. 6.7  Electrical Characteristics: VS = 3 V
    8. 6.8  Typical Characteristics: VS = ±5 V
    9. 6.9  Typical Characteristics: VS = 3 V
    10. 6.10 Typical Characteristics: VS = 3 V to 10 V
  8. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Input Stage
      2. 7.3.2 Output Stage
        1. 7.3.2.1 Overload Power Limit
      3. 7.3.3 ESD Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 Power-Down Mode
  9. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Active Filters
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Low-Power SAR ADC Driver and Reference Buffer
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. Device and Documentation Support
    1. 9.1 Documentation Support
      1. 9.1.1 Related Documentation
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • DSN|10
Thermal pad, mechanical data (Package|Pins)
Orderable Information

Detailed Design Procedure

Figure 8-1 shows the use of OPAx863A in a second-order multifeedback (MFB) low-pass filter with a cut-off frequency of 2 MHz. The frequency response of the circuit in Figure 8-1 is compared for various amplifiers with different gain-bandwidth products and shown in Figure 8-2:

GUID-20221212-SS0I-GMB8-WC7K-NCHW7GSTBCMV-low.svg Figure 8-1 MFB Low-Pass Filter Circuit Using the OPAx863A
Table 8-1 Impact of Amplifier GBW on Cutoff Frequency
DEVICE GBW (MHz) CUTOFF FREQUENCY (MHz)
TLV9051 5 1.59
LMV641 10 1.78
OPA2834 20 1.87
OPAx863A 50 1.95
OPA836 110 1.98

Table 8-1 provides the following benefits of using OPAx863A in an MFB low-pass filter circuit:

  • High-precision measurements with low offset voltage across the operating temperature range for low-frequency signals in pass band
  • High linearity due to the larger GBW and loop gain for low-frequency signals in pass band
  • Higher accuracy of cutoff frequency and smaller variations over process and temperature
  • Small integrated output noise due to low-pass filtering

Based on Figure 8-2, and as with the OPAx863A, use an amplifier with a gain bandwidth product at least 20 × greater than the filter cutoff frequency. This configuration results in a high-precision and high-linearity, low-pass-filter design.