SBOS831B December   2016  – June 2021 THS4552

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics: (VS+) – (VS–) = 5 V
    6. 6.6 Electrical Characteristics: (VS+) – (VS–) = 3 V
    7. 6.7 Typical Characteristics: (VS+) – (VS–) = 5 V
    8. 6.8 Typical Characteristics: (VS+) – (VS–) = 3 V
    9. 6.9 Typical Characteristics: 3 V to 5 V Supply Range
  7. 7 Parameter Measurement Information
    1. 7.1 Example Characterization Circuits
    2. 7.2 Output Interface Circuit for DC-Coupled Differential Testing
    3. 7.3 Output Common-Mode Measurements
    4. 7.4 Differential Amplifier Noise Measurements
    5. 7.5 Balanced Split-Supply Versus Single-Supply Characterization
    6. 7.6 Simulated Characterization Curves
    7. 7.7 Terminology and Application Assumptions
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Differential Open-Loop Gain and Output Impedance
      2. 8.3.2 Setting Resistor Values Versus Gain
      3. 8.3.3 I/O Headroom Considerations
      4. 8.3.4 Output DC Error and Drift Calculations and the Effect of Resistor Imbalances
    4. 8.4 Device Functional Modes
      1. 8.4.1 Operation from Single-Ended Sources to Differential Outputs
        1. 8.4.1.1 AC-Coupled Signal Path Considerations for Single-Ended Input to Differential Output Conversions
        2. 8.4.1.2 DC-Coupled Input Signal Path Considerations for Single-Ended to Differential Conversions
      2. 8.4.2 Operation from a Differential Input to a Differential Output
        1. 8.4.2.1 AC-Coupled, Differential-Input to Differential-Output Design Issues
        2. 8.4.2.2 DC-Coupled, Differential-Input to Differential-Output Design Issues
      3. 8.4.3 Input Overdrive Performance
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Noise Analysis
      2. 9.1.2 Factors Influencing Harmonic Distortion
      3. 9.1.3 Driving Capacitive Loads
      4. 9.1.4 Interfacing to High-Performance Precision ADCs
      5. 9.1.5 Operating the Power Shutdown Feature
      6. 9.1.6 Channel-to-Channel Crosstalk
      7. 9.1.7 Channel-to-Channel Mismatch
      8. 9.1.8 Designing Attenuators
      9. 9.1.9 The Effect of Adding a Feedback Capacitor
    2. 9.2 Typical Applications
      1. 9.2.1 An MFB Filter Driving an ADC Application
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
        3. 9.2.1.3 Application Curves
      2. 9.2.2 Differential Transimpedance Output to a High-Grade Audio PCM DAC Application
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
        3. 9.2.2.3 Application Curves
      3. 9.2.3 ADC3k Driver with a 2nd-Order RLC Interstage Filter Application
        1. 9.2.3.1 Design Requirements
        2. 9.2.3.2 Detailed Design Procedure
        3. 9.2.3.3 Application Curve
  10. 10Power Supply Recommendations
    1. 10.1 Thermal Analysis
  11. 11Layout
    1. 11.1 Layout Guidelines
      1. 11.1.1 Board Layout Recommendations
    2. 11.2 Layout Example
    3. 11.3 EVM Board
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 TINA-TI Simulation Model Features
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 Support Resources
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

10.1 Thermal Analysis

The very low internal quiescent power dissipation for the THS4552, combined with the excellent thermal impedance of the 24-pin VQFN package (RTW), limits the possibility of excessively high internal junction temperatures.

To estimate the internal TJ, an estimate of the maximum internal power dissipation is first required. There are two pieces to the internal power dissipation: quiescent current power and the power used in the output stage to deliver load current. To simplify the latter, the worst-case output stage power drives a dc differential voltage across a load using half the total supply voltage. Also assume a maximum ambient temperature of 125°C, giving the maximum quiescent current as shown in Figure 10-1. As an example:

  • Assume a maximum operating supply voltage of 5.4 V. This 5.4 V supply with a maximum ICC of 1.46 mA/channel gives a quiescent power term of 2 × 1.46 mA × 5.4 V = 15.77 mW.
  • Assume a 200 Ω differential load with a static 2.7 V differential voltage established across the load for both channels. The 1.35 mA of dc load current generates a maximum output stage power of (5.4 V – 2.7 V) × 1.35 mA = 3.65 mW/channel and a total power dissipation of 7.3 mW for both channels.
  • From the worst-case total internal PD of 23.07 mW, multiplying the internal PD with a 46°C/W thermal impedance for the 24-pin VQFN package results in a 1.06°C rise from ambient.

Even for this extreme condition and the maximum-rated ambient of 125°C, the junction temperature is a maximum of 126°C, which is less than the rated absolute maximum of 150°C. Follow this same calculation sequence for the exact application and package selected to predict the maximum TJ.