SBOS982E June   2020  – November 2021 OPA2863 , OPA4863 , OPA863

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Device Comparison Table
  6. Pin Configuration and Functions
  7. Specifications
    1. 7.1  Absolute Maximum Ratings
    2. 7.2  ESD Ratings
    3. 7.3  Recommended Operating Conditions
    4. 7.4  Thermal Information: OPA863
    5. 7.5  Thermal Information: OPA2863
    6. 7.6  Thermal Information: OPA4863
    7. 7.7  Electrical Characteristics: 10 V
    8. 7.8  Electrical Characteristics: 3 V
    9. 7.9  Typical Characteristics: VS = 10 V
    10. 7.10 Typical Characteristics: VS = 3 V
    11. 7.11 Typical Characteristics: VS = 3 V to 10 V
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Input Stage
      2. 8.3.2 Output Stage
        1. 8.3.2.1 Overload Power Limit
      3. 8.3.3 ESD Protection
    4. 8.4 Device Functional Modes
      1. 8.4.1 Power-Down Mode
  9. Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Low-Side Current Sensing
      1. 9.2.1 Design Requirements
    3. 9.3 Front-End Gain and Filtering
    4. 9.4 Low-Power SAR ADC Driver and Reference Buffer
    5. 9.5 Variable Reference Generator Using MDAC
    6. 9.6 Clamp-On Ultrasonic Flow Meter
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
      1. 11.1.1 Thermal Considerations
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 Receiving Notification of Documentation Updates
    3. 12.3 Support Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

Clamp-On Ultrasonic Flow Meter

Figure 9-6 shows how ultrasonic flow meters measure the rate of flow of a liquid using transit-time difference (t12–t21), which depends on the flow rate. Figure 9-6 shows a representative schematic for a non-intrusive ultrasonic flow meter using the OPAx863 devices and 12-V transducer excitation. The OPAx863 devices are used for the forward path as a unity-gain buffer for 12-V pulsed transducer excitation at Node 1. At the same time, the receiver circuit at Node 2, also using the OPAx863 devices, first provides an AC-gain followed by a DC-level shift to lead to the PGA, ADC and processing within the MSP430 microcontroller.

Node 2 and Node 1 use similar transmit and receive circuits (discussed above) for the reverse path. The OPAx863 devices wide GBW of 50 MHz introduces minimal phase-delay and low-noise for superior flow rate measurement. The amplifier stays in power-down mode for a majority of the time in battery powered systems, resulting in very small average system-level power consumption and prolonged battery lifetime with its 1.5 µA (maximum) power-down mode quiescent current with a 3-V supply. Since the transmit and receive signal chains are connected to the same point at the respective node transducers, the OPAx863's 12.6-V supply voltage capability enables 12-V transducer excitation without any damage to the front-end or need for external switches which makes a compact solution. This makes the OPAx863 devices suitable for flow measurements in large diameter pipes and non-intrusive flow meters. The TIDM-02003 reference design discusses an ultrasonic gas flow sensing subsystem which uses high-speed amplifiers for front-end amplification.

GUID-76FEEB03-A2DE-455F-A925-B66249FDBF0B-low.gif Figure 9-6 Non-Intrusive Ultrasonic Flow Meter