SBOSA28A August   2023  – December 2024 LOG200

PRODMIX  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 High Speed, Logarithmic Current-to-Voltage Conversion
      2. 6.3.2 Voltage and Current References
      3. 6.3.3 Adaptive Photodiode Bias
      4. 6.3.4 Auxiliary Operational Amplifier
    4. 6.4 Device Functional Modes
  8. 7 Application and Implementation
    1. 7.1 Application Information
      1. 7.1.1 Logarithmic Transfer Function
        1. 7.1.1.1 Logarithmic Conformity Error
        2. 7.1.1.2 Error Analysis Example
    2. 7.2 Typical Application
      1. 7.2.1 Optical Current Sensing
        1. 7.2.1.1 Design Requirements
        2. 7.2.1.2 Detailed Design Procedure
        3. 7.2.1.3 Application Curves
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Third-Party Products Disclaimer
    2. 8.2 Documentation Support
      1. 8.2.1 Related Documentation
    3. 8.3 Receiving Notification of Documentation Updates
    4. 8.4 Support Resources
    5. 8.5 Trademarks
    6. 8.6 Electrostatic Discharge Caution
    7. 8.7 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • RGT|16
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7.2.1.3 Application Curves

The following figures show oscilloscope captures of the LOG200 output as the device responds to one-decade shifts in the input current. Rising and falling steps between 10nA and 100nA, and between 10µA and 100µA, were recorded. The oscilloscope was set to use the ac-coupled path.

For the current steps between 10nA and 100nA, a 10mA laser diode bias was used. A rise time of approximately 268ns and a fall time of approximately 626ns are observed.

LOG200 10nA-to-100nA Current StepFigure 7-6 10nA-to-100nA Current Step
LOG200 100nA-to-10nA Current StepFigure 7-7 100nA-to-10nA Current Step

For the current steps between 10µA and 100µA, a 13mA laser diode bias was used. A rise time of approximately 45.60ns and a fall time of approximately 55.60ns are observed.

LOG200 10µA-to-100µA Current StepFigure 7-8 10µA-to-100µA Current Step
LOG200 100µA-to-10µA Current StepFigure 7-9 100µA-to-10µA Current Step