SBOSA28B August   2023  – August 2026 LOG200

PRODUCTION DATA  

  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

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

3 Description

The LOG200 is a wide-dynamic-range current-to-voltage amplifier specifically designed to optimize current measurements across 160dB of dynamic range with unparalleled accuracy and speed for optical communications, medical diagnostics, and industrial process-control measurements. The LOG200 features two logarithmic amplifiers followed by a high-accuracy differential amplifier that convert current signals into a voltage representing the log-compressed ratio of the two currents. The current inputs are designed to feature a high-speed response from one input, and a highly accurate reference signal on the other input, allowing for a unique combination of fast transient response and high logarithmic conformity.

The LOG200 ratio is internally set to 250mV/decade of current-to-voltage conversion. The device integrates an uncommitted high-speed amplifier to allow the output to be configured for differential or filtered responses, with a fast settling time to drive successive approximation analog-to-digital converters (SAR ADCs). The LOG200 also features a separate reference current and reference voltage designed to configure the device for optimized input current and common-mode voltages.

The LOG200 can be powered in a single-supply (4.5V to 12.6V) or dual-supply (±2.25V to ±6.3V) configuration and is specified from –40°C to +125°C.

Package Information
PART NUMBERPACKAGE(1)PACKAGE SIZE(2)
LOG200RGT (VQFN, 16)3mm × 3mm
YBH (DSBGA, 16)1.6mm × 1.6mm
(1) For more information, see Section 10.
(2) The package size (length × width) is a nominal value and includes pins, where applicable.