SNIS139F February   2005  – January 2024 LM95231

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 Operating Ratings
    3. 5.3 Temperature-to-Digital Converter Characteristics
    4. 5.4 Logic Electrical Characteristics Digital DC Characteristics
    5. 5.5 Logic Electrical Characteristics SMBus Digital Switching Characteristics
    6. 5.6 Typical Performance Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Conversion Sequence
      2. 6.3.2 Power-On-Default States
      3. 6.3.3 SMBus Interface
      4. 6.3.4 Temperature Data Format
      5. 6.3.5 SMBDAT Open-Drain Output
      6. 6.3.6 Diode Fault Detection
      7. 6.3.7 Communicating with the LM95231
      8. 6.3.8 Serial Interface Reset
      9. 6.3.9 One-Shot Conversion
  8. 7 Registers
    1. 7.1 LM95231 Registers
    2. 7.2 Status Register
    3. 7.3 Configuration Register
    4. 7.4 Remote Diode Filter Control Register
    5. 7.5 Remote Diode Model Type Select Register
    6. 7.6 Remote TruTherm Mode Control
    7. 7.7 Local and Remote MSB and LSB Temperature Registers
      1. 7.7.1 Local Temperature MSB
      2. 7.7.2 Local Temperature LSB
      3. 7.7.3 Remote Temperature MSB
      4. 7.7.4 Remote Temperature LSB
    8. 7.8 Manufacturers ID Register
    9. 7.9 Die Revision Code Register
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Diode Non-Ideality
        1. 8.2.1.1 Diode Non-Ideality Factor Effect on Accuracy
        2. 8.2.1.2 Calculating Total System Accuracy
        3. 8.2.1.3 Compensating for Different Non-Ideality
  10. 9 Layout
    1. 9.1 PCB Layout for Minimizing Noise
  11. 10Device and Documentation Support
    1. 10.1 Documentation Support
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

Package Options

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

5.3 Temperature-to-Digital Converter Characteristics

Unless otherwise noted, these specifications apply for VDD=+3.0Vdc to 3.6Vdc. Boldface limits apply for TA = TJ = TMIN≤TA≤TMAX; all other limits TA= TJ=+25°C, unless otherwise noted. TJ is the junction temperature of the LM95231. TD is the junction temperature of the remote thermal diode.
PARAMETER TEST CONDITIONS Typical(1) LM95231
BIMM
Limits(4)		 LM95231
CIMM
Limits(4)		 UNIT
Accuracy Using Local Diode TA = 0°C to +85°C(3)(7) ±1 ±3 ±3 °C (max)
Accuracy Using Remote Diode, see(5) for Thermal Diode Processor Type. TA = +20°C to +40°C; TD = +45°C to +85°C Intel 90nm Thermal Diode ±0.75 °C (max)
TA = +20°C to +40°C; TD = +45°C to +85°C MMBT3904 Thermal Diode ±1.25 °C (max)
TA = +20°C to +40°C; TD = +45°C to +85°C Intel 90nm and MMBT3904 Thermal Diodes ±1.25 °C (max)
TA = +0°C to +85°C; TD = +25°C to +140°C Intel 90nm and MMBT3904 Thermal Diodes ±2.5 ±2.5 °C (max)
Remote Diode Measurement Resolution with filtering turned off 10+sign/11 Bits
0.125 °C
Remote Diode Measurement Resolution with digital filtering turned on 12+sign/13 Bits
0.03125 °C
Local Diode Measurement Resolution 9+sign Bits
0.25 °C
Conversion Time of All Temperatures at the Fastest Setting See(6) TruTherm Mode Disabled 75.8 83.9 83.9 ms (max)
TruTherm Mode enabled 79.2 87.7 87.7 ms (max)
Average Quiescent Current(7) SMBus Inactive, 1 Hz conversion rate 402 545 545 µA (max)
Shutdown 272 µA
D− Source Voltage 0.4 V
Diode Source Current Ratio 16
Diode Source Current (VD+ − VD−) = + 0.65V;
high-level		 176 300 300 µA (max)
100 100 µA (min)
Low-level 11 µA
Power-On Reset Threshold Measure on VDD input, falling edge 2.7
1.8		 2.7
1.8		 V (max)
V (min)
(1) Typicals are at TA = 25°C and represent most likely parametric norm at time of product characterization. The typical specifications are not ensured.
(4) Limits are specified to AOQL (Average Outgoing Quality Level).
(3) Local temperature accuracy does not include the effects of self-heating. The rise in temperature due to self-heating is the product of the internal power dissipation of the LM95231 and the thermal resistance. See Note 2 of the Operating Ratings table for the thermal resistance to be used in the self-heating calculation.
(7) Thermal resistance junction-to-ambient when attached to a printed circuit board with 1oz. foil and no airflow:
— VSSOP-8 = 210°C/W
(5) The accuracy of the LM95231 is ensured when using the thermal diode of Pentium 4 processor on 90nm process or an MMBT3904 type transistor, as selected in the Remote Diode Model Select register.
(6) This specification is provided only to indicate how often temperature data is updated. The LM95231 can be read at any time without regard to conversion state (and will yield last conversion result).
(7) Quiescent current will not increase substantially when the SMBus is active.