SNIS128D August   2002  – June 2014 LM89

UNLESS OTHERWISE NOTED, this document contains ADVANCE INFORMATION for pre-production products; subject to change without notice.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Remote Diode Temperature Sensor System Diagram
  5. 5 Revision History
  6. 6 Device Comparison Table
  7. 7 Pin Configuration And Functions
  8. 8 Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 Handling Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Temperature-To-Digital Converter Characteristics
    6. 8.6 Digital DC Characteristics
    7. 8.7 Timing Requirements
    8. 8.8 SMBus Digital Switching Characteristics
    9. 8.9 Typical Characteristics
  9. 9  Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1  Conversion Sequence
      2. 9.3.2  The ALERT Output
        1. 9.3.2.1 ALERT Output As A Temperature Comparator
        2. 9.3.2.2 ALERT Output As An Interrupt
        3. 9.3.2.3 ALERT Output As An SMBus Alert
      3. 9.3.3  T_CRIT_A Output And T_CRIT Limit
      4. 9.3.4  Smbus Interface
      5. 9.3.5  Temperature Data Format
      6. 9.3.6  Open-Drain Outputs
      7. 9.3.7  Diode Fault Detection
      8. 9.3.8  Communicating With The LM89
        1. 9.3.8.1 SMBus Timing Diagrams
      9. 9.3.9  Serial Interface Reset
      10. 9.3.10 Digital Filter
      11. 9.3.11 Fault Queue
      12. 9.3.12 One-Shot Register
    4. 9.4 Device Functional Modes
      1. 9.4.1 Power-On-Default States
    5. 9.5 Programming
    6. 9.6 Register Maps
      1. 9.6.1  Command Register
      2. 9.6.2  Local And Remote Temperature Registers (LT, RTHB, RTLB)
      3. 9.6.3  Status Register (SR)
      4. 9.6.4  Configuration Register
      5. 9.6.5  Conversion Rate Register
      6. 9.6.6  Local And Remote High Setpoint Registers (LHS, RHSHB, And RHSLB)
      7. 9.6.7  Local And Remote Low Setpoint Registers (LLS, RLSHB, And RLSLB)
      8. 9.6.8  Remote Temperature Offset Registers (RTOHB And RTOLB)
      9. 9.6.9  Local And Remote T_crit Registers (RCS And LCS)
      10. 9.6.10 T_CRIT Hysteresis Register (TH)
      11. 9.6.11 Filter And Alert Configure Register
      12. 9.6.12 Manufacturers Id Register
      13. 9.6.13 Die Revision Code Register
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
        1. 10.2.1.1 Diode Nonideality
          1. 10.2.1.1.1 Diode Nonideality Factor Effect On Accuracy
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 Compensating For Diode Nonideality
      3. 10.2.3 Application Curves
    3. 10.3 Do's and Don'ts
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Trademarks
    2. 13.2 Electrostatic Discharge Caution
    3. 13.3 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

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

11 Power Supply Recommendations

VDD should be bypassed with a 0.1µF capacitor in parallel with 100pF. The 100pF capacitor should be placed as close as possible to the power supply pin. A bulk capacitance of approximately 10µF needs to be in the near vicinity of the LM89. The ideal place to connect the LM89's GND pin is as close as possible to the Processors GND associated with the sense diode.