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

7 Pin Configuration And Functions

8-Pin VSSOP or SOIC
DGK or D Packages
(TOP VIEW)
20041502.png

Pin Functions

PIN DESCRIPTION
NAME DGK or D NUMBER FUNCTION TYPICAL CONNECTION
VDD 1 Positive Supply Voltage Input DC Voltage from 3.0 V to 3.6 V. 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 to the LM89 VDD.
D+ 2 Diode Current Source To Diode Anode. Connected to remote discrete diode-connected transistor junction or to the diode-connected transistor junction on a remote IC whose die temperature is being sensed. A 2.2 nF diode bypass capacitor is required to filter high frequency noise. Place the 2.2 nF capacitor between and as close as possible to the LM89's D+ and D− pins. Make sure the traces to the 2.2 nF capacitor are matched.
D− 3 Diode Return Current Sink To Diode Cathode.
T_CRIT_A 4 T_CRIT Alarm Output, Open-Drain, Active-Low Pull-Up Resistor, Controller Interrupt or Power Supply Shutdown Control
GND 5 Power Supply Ground Ground
ALERT 6 Interrupt Output, Open-Drain, Active-Low Pull-Up Resistor, Controller Interrupt or Alert Line
SMBData 7 SMBus Bi-Directional Data Line, Open-Drain Output From and to Controller, Pull-Up Resistor
SMBCLK 8 SMBus Input From Controller, Pull-Up Resistor

Table 1. ESD Protection(1)

Pin Name PIN NO. D1 D2 D3 D4 D5 D6 D7 R1 SNP ESD CLAMP
VDD 1 x
D+ 2 x x x x x x
D− 3 x x x x x x
T_CRIT_A 4 x x x
ALERT 6 x x x
SMBData 7 x x x
SMBCLK 8 x
(1) An “x” indicates that the component exists.
20041513.gifFigure 1. ESD Protection Input Structure