SNAS207B May   2004  – January 2024 LM64

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 DC Electrical Characteristics
    4. 5.4 Operating Electrical Characteristics
    5. 5.5 AC Electrical Characteristics
    6. 5.6 Digital Electrical Characteristics
    7. 5.7 SMBus Logical Electrical Characteristics
    8. 5.8 SMBus Digital Switching 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  The ALERT Output
        1. 6.3.2.1 ALERT Output as a Temperature Comparator
        2. 6.3.2.2 ALERT Output as an Interrupt
        3. 6.3.2.3 ALERT Output as an SMBus ALERT
      3. 6.3.3  SMBus Interface
      4. 6.3.4  Power-On Reset (POR) Default States
      5. 6.3.5  Temperature Data Format
      6. 6.3.6  Open-Drain Outputs, Inputs, and Pull-Up Resistors
      7. 6.3.7  Diode Fault Detection
      8. 6.3.8  Communicating with the LM64
      9. 6.3.9  Digital Filter
      10. 6.3.10 Fault Queue
      11. 6.3.11 One-Shot Register
      12. 6.3.12 Serial Interface Reset
  8. 7 Registers
    1. 7.1 LM64 Registers
      1. 7.1.1 LM64 Register Map in Hexadecimal Order
      2. 7.1.2 LM64 Register Map in Functional Order
      3. 7.1.3 LM64 Initial Register Sequence and Register Descriptions in Functional Order
        1. 7.1.3.1 LM64 Required Initial Fan Control Register Sequence
      4. 7.1.4 LM64 Register Descriptions in Functional Order
        1. 7.1.4.1 Fan Control Registers
        2. 7.1.4.2 Configuration Register
        3. 7.1.4.3 Tachometer Count And Limit Registers
        4. 7.1.4.4 Local Temperature And Local High Setpoint Registers
        5. 7.1.4.5 Remote Diode Temperature, Offset And Setpoint Registers
        6. 7.1.4.6 ALERT Status And Mask Registers
        7. 7.1.4.7 Conversion Rate And One-Shot Registers
        8. 7.1.4.8 ID Registers
    2. 7.2 General Purpose Registers
  9. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Fan Control Duty Cycle VS. Register Settings and Frequency
        1. 8.1.1.1 Computing Duty Cycles for a Given Frequency
      2. 8.1.2 Use of the Lookup Table for Non-Linear PWM Values VS Temperature
      3. 8.1.3 NON-Ideality Factor and Temperature Accuracy
        1. 8.1.3.1 Diode Non_Ideality
        2. 8.1.3.2 Compensating for Diode Non-Ideality
      4. 8.1.4 Computing RPM of the Fan from the TACH Count
    2. 8.2 Typical Application
  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

7.1.1 LM64 Register Map in Hexadecimal Order

The following is a Register Map grouped in hexadecimal address order. Some address locations have been left blank to maintain compatibility with LM86. Addresses in parenthesis are mirrors of “Same As” address for backwards compatibility with some older software. Reading or writing either address will access the same 8-bit register.

Register
0x[HEX]		 Register Name DATA BITS
D7 D6 D5 D4 D3 D2 D1 D0
00 Local Temperature LT7 LT6 LT5 LT4 LT3 LT2 LT1 LT0
01 Rmt Temp MSB RTHB± RTHB14 RTHB13 RTHB12 RTHB11 RTHB10 RTHB9 RTHB8
02 ALERT Status BUSY LHIGH 0 RHIGH RLOW RDFA RCRIT TACH
03 Configuration ALTMSK STBY PWMDIS 0 0 ALT/TCH TCRITOV FLTQUE
04 Conversion Rate 0 0 0 0 CONV3 CONV2 CONV1 CONV0
05 Local High Setpoint LHS7 LHS6 LHS5 LHS4 LHS3 LHS2 LHS1 LHS0
06 [Reserved] Not Used
07 Rmt High Setpoint MSB RHSHB15 RHSHB14 RHHBS13 RHSHB12 RHSHB11 RHSHB10 RHSHB9 RHSHB8
08 Rmt Low Setpoint MSB RLSHB15 RLSHB14 RLSHB13 RLSHB12 RLHBS11 RLSHB10 RLSHB9 RLSHB8
(09) Same as 03
(0A) Same as 04
(0B) Same as 05
0C [Reserved] Not Used
(0D) Same as 07
(0E) Same as 08
0F One Shot Write Only. Write command triggers one temperature conversion cycle.
10 Rmt Temp LSB RTLB7 RTLB6 RTLB5 0 0 0 0 0
11 Rmt Temp Offset MSB RTOHB15 RTOHB14 RTOHB13 RTOHB12 RTOHB11 RTOHB10 RTOHB9 RTOHB8
12 Rmt Temp Offset LSB RTOLB7 RTOLB6 RTOLB5 0 0 0 0 0
13 Rmt High Setpoint LSB RHSLB7 RHSLB6 RHSLB5 0 0 0 0 0
14 Rmt Low Setpoint LSB RLSLB7 RLSLB6 RLSLB5 0 0 0 0 0
15 [Reserved] Not Used
16 ALERT Mask 1 ALTMSK6 1 ALTMSK4 ALTMSK3 1 ALTMSK1 ALTMSK0
17 [Reserved] Not Used
18 [Reserved] Not Used
19 Rmt TCRIT Setpoint RCS7 RCS6 RCS5 RCS4 RCS3 RCS2 RCS1 RCS0
1A General Purpose Input 0 0 0 GPI5 GPI4 GPI3 GPI2 GPI1
1B General Purpose Output 0 0 0 GPO5 GPO4 GPO3 GPO2 GPO1
1C–1F [Reserved] Not Used
20 [Reserved] Not Used
21 Rmt TCRIT Hysteresis RTH7 RTH6 RTH5 RTH4 RTH3 RTH2 RTH1 RTH0
22–2F [Reserved] Not Used
30–3F [Reserved] Not Used
40–45 [Reserved] Not Used
46 Tach Count LSB TCLB5 TCLB4 TCLB3 TCLB2 TCLB1 TCLB0 TEDGE1 TEDGE0
47 Tach Count MSB TCHB13 TCHB12 TCHB11 TCHB10 TCHB9 TCHB8 TCHB7 TCHB6
48 Tach Limit LSB TLLB7 TLLB6 TLLB5 TLLB4 TLLB3 TLLB2 Not Used Not Used
49 Tach Limit MSB TLHB15 TLHB14 TLHB13 TLHB12 TLHB11 TLHB10 TLHB9 TLHB8
4A PWM and RPM 0 0 PWPGM PWOUT± PWCKSL 0 TACH1 TACH0
4B Fan Spin-Up Config 0 0 SPINUP SPNDTY1 SPNDTY0 SPNUPT2 SPNUPT1 SPNUPT0
4C PWM Value 0 0 PWVAL5 PWVAL4 PWVAL3 PWVAL2 PWVAL1 PWVAL0
4D PWM Frequency 0 0 0 PWMF4 PWMF3 PWMF2 PWMF1 PWMF0
4E [Reserved] Not Used
4F Lookup Table Hystersis 0 0 0 LOOKH4 LOOKH3 LOOKH2 LOOKH1 LOOKH0
50–5F Lookup Table Lookup Table of up to 8 PWM and Temp Pairs in 8-bit Registers
60–BE [Reserved] Not Used
BF Rmt Diode Temp Filter 0 0 0 0 0 RDTF1 RDTF0 ALTCOMP
C0–FD [Reserved] Not Used
FE Manufacturer’s ID 0 0 0 0 0 0 0 1
FF Stepping/Die Rev. ID 0 1 0 1 0 0 0 1