EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation PRODUCT FEATURES Datasheet General Description Applications The EMC1412 is a high accuracy, low cost, System Management Bus (SMBus) temperature sensor. Advanced features such as Resistance Error Correction (REC), Beta Compensation (to support CPU diodes requiring the BJT/transistor model including 45nm, 65nm and 90nm processors) and automatic diode type detection combine to provide a robust solution for complex environmental monitoring applications. The EMC1412 monitors two temperature channels (one external and one internal). It provides ±1°C accuracy for both external and internal diode temperatures. Resistance Error Correction automatically eliminates the temperature error caused by series resistance allowing greater flexibility in routing thermal diodes. Beta Compensation eliminates temperature errors caused by low, variable beta transistors common in today's fine geometry processors. The automatic beta detection feature monitors the external diode/transistor and determines the optimum sensor settings for accurate temperature measurements regardless of processor technology. This frees the user from providing unique sensor configurations for each temperature monitoring application. These advanced features plus ±1°C measurement accuracy provide a low-cost, highly flexible and accurate solution for critical temperature monitoring applications. SMSC EMC1412 Notebook Computers Desktop Computers Industrial Embedded applications Features Programmable SMBus address Support for diodes requiring the BJT/transistor model — supports 45nm, 65nm, and 90nm CPU thermal diodes Automatically determines external diode type and optimal settings Resistance Error Correction External Temperature Monitor — ±1°C max accuracy (20°C < TDIODE < 110°C) — 0.125°C resolution — Supports up to 2.2nF diode filter capacitor Internal Temperature Monitor — ±1°C accuracy — 0.125°C resolution 3.3V Supply Voltage Programmable temperature limits for ALERT and THERM Available in small 8-pin 2mm x 3mm TDFN lead-free RoHS compliant package Available in small 8-pin MSOP lead-free RoHS compliant package DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Ordering Information: ORDERING NUMBER PACKAGE FEATURES SMBUS ADDRESS EMC1412-A-ACZL-TR 8-pin MSOP (lead-free RoHS compliant Two temperature sensors, ALERT and THERM pins, programmable SMBus address Selectable via THERM pull-up EMC1412-A-AC3-TR 8-pin TDFN 2mm x 3mm (lead-free RoHS compliant Two temperature sensors, ALERT and THERM pins, fixed SMBus address Selectable via THERM pull-up EMC1412-1-ACZL-TR 8-pin MSOP (lead-free RoHS compliant Two temperature sensors, ALERT and THERM pins, fixed SMBus address 1001_100(r/w) EMC1412-1-AC3-TR 8-pin TDFN 2mm x 3mm (lead-free RoHS compliant Two temperature sensors, ALERT and THERM pins, fixed SMBus address 1001_100(r/w) EMC1412-2-ACZL-TR 8-pin MSOP (lead-free RoHS compliant Two temperature sensors, ALERT and THERM pins, fixed SMBus address 1001_101(r/w) REEL SIZE IS 4,000 PIECES FOR THE MSOP REEL SIZE IS 5,000 PIECES FOR THE TDFN This product meets the halogen maximum concentration values per IEC61249-2-21 For RoHS compliance and environmental information, please visit www.smsc.com/rohs 80 ARKAY DRIVE, HAUPPAUGE, NY 11788 (631) 435-6000 or 1 (800) 443-SEMI Copyright © 2012 SMSC or its subsidiaries. All rights reserved. Circuit diagrams and other information relating to SMSC products are included as a means of illustrating typical applications. Consequently, complete information sufficient for construction purposes is not necessarily given. Although the information has been checked and is believed to be accurate, no responsibility is assumed for inaccuracies. SMSC reserves the right to make changes to specifications and product descriptions at any time without notice. Contact your local SMSC sales office to obtain the latest specifications before placing your product order. The provision of this information does not convey to the purchaser of the described semiconductor devices any licenses under any patent rights or other intellectual property rights of SMSC or others. All sales are expressly conditional on your agreement to the terms and conditions of the most recently dated version of SMSC's standard Terms of Sale Agreement dated before the date of your order (the "Terms of Sale Agreement"). The product may contain design defects or errors known as anomalies which may cause the product's functions to deviate from published specifications. Anomaly sheets are available upon request. SMSC products are not designed, intended, authorized or warranted for use in any life support or other application where product failure could cause or contribute to personal injury or severe property damage. Any and all such uses without prior written approval of an Officer of SMSC and further testing and/or modification will be fully at the risk of the customer. Copies of this document or other SMSC literature, as well as the Terms of Sale Agreement, may be obtained by visiting SMSC’s website at http://www.smsc.com. SMSC is a registered trademark of Standard Microsystems Corporation (“SMSC”). Product names and company names are the trademarks of their respective holders. SMSC DISCLAIMS AND EXCLUDES ANY AND ALL WARRANTIES, INCLUDING WITHOUT LIMITATION ANY AND ALL IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE, AND AGAINST INFRINGEMENT AND THE LIKE, AND ANY AND ALL WARRANTIES ARISING FROM ANY COURSE OF DEALING OR USAGE OF TRADE. IN NO EVENT SHALL SMSC BE LIABLE FOR ANY DIRECT, INCIDENTAL, INDIRECT, SPECIAL, PUNITIVE, OR CONSEQUENTIAL DAMAGES; OR FOR LOST DATA, PROFITS, SAVINGS OR REVENUES OF ANY KIND; REGARDLESS OF THE FORM OF ACTION, WHETHER BASED ON CONTRACT; TORT; NEGLIGENCE OF SMSC OR OTHERS; STRICT LIABILITY; BREACH OF WARRANTY; OR OTHERWISE; WHETHER OR NOT ANY REMEDY OF BUYER IS HELD TO HAVE FAILED OF ITS ESSENTIAL PURPOSE, AND WHETHER OR NOT SMSC HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. Revision 1.41 (02-23-12) 2 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Table of Contents Chapter 1 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Chapter 2 Delta . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2.1 Functional Delta from EMC1412 rev A to rev B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Chapter 3 Pin Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Chapter 4 Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 4.1 4.2 4.3 Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 SMBus Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Chapter 5 System Management Bus Interface Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 5.1 5.2 5.3 Communications Protocol. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.1 SMBus Start Bit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.2 SMBus Address and RD / WR Bit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.3 THERM Pin Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.4 SMBus Data Bytes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.5 SMBus ACK and NACK Bits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.6 SMBus Stop Bit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.7 SMBus Timeout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.8 SMBus and I2C Compatibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SMBus Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.1 Write Byte . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.2 Read Byte . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.3 Send Byte . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.4 Receive Byte . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Alert Response Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 13 13 14 14 14 15 15 15 15 15 16 16 16 16 Chapter 6 Product Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 6.9 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.1 Conversion Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.2 Dynamic Averaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . THERM Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ALERT Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3.1 ALERT Pin Interrupt Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3.2 ALERT Pin Comparator Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Temperature Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.4.1 Beta Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.4.2 Resistance Error Correction (REC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.4.3 Programmable External Diode Ideality Factor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Diode Faults . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Consecutive Alerts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Digital Filter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Temperature Measurement Results and Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . External Diode Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 18 19 19 20 20 20 20 20 21 21 21 21 21 23 24 Chapter 7 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 7.1 7.2 Data Read Interlock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Temperature Data Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 SMSC EMC1412 3 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet 7.3 7.4 7.5 7.6 7.7 7.8 7.9 7.10 7.11 7.12 7.13 7.14 7.15 7.16 7.17 Status Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Conversion Rate Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Limit Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Scratchpad Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . One Shot Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Therm Limit Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Channel Mask Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Consecutive ALERT Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Beta Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . External Diode Ideality Factor Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Filter Control Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Product ID Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SMSC ID Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Revision Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 28 29 30 30 31 31 31 32 33 34 36 36 36 37 Chapter 8 Typical Operating Curves. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Chapter 9 Package Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 9.1 Package Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Chapter 10 Document Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 Revision 1.41 (02-23-12) 4 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet List of Figures Figure 1.1 Figure 3.1 Figure 3.2 Figure 5.1 Figure 5.2 Figure 6.1 Figure 6.2 Figure 6.3 Figure 6.4 Figure 9.1 Figure 9.2 Figure 9.3 Figure 9.4 Figure 9.5 Figure 9.6 Figure 9.7 EMC1412 Block Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 EMC1412 Pin Diagram, MSOP-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 EMC1412 Pin Diagram, TDFN-8 2mm x 3mm. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 SMBus Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Isolating THERM Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 System Diagram for EMC1412 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Temperature Filter Step Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Temperature Filter Impulse Response. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Diode Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 EMC1412 2mm x 3mm TDFN Package Drawing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 EMC1412 2mm x 3mm TDFN Package Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 EMC1412 2mm x 3mm TDFN Package PCB Land Pattern. . . . . . . . . . . . . . . . . . . . . . . . . . 41 8-Pin MSOP / TSSOP Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 EMC1412-1 8-Pin TDFN Package Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 EMC1412-A 8-Pin TDFN Package Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 EMC1412 8-Pin MSOP Package Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 SMSC EMC1412 5 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet List of Tables Table 3.1 EMC1412 Pin Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Table 3.2 Pin Types. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Table 4.1 Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Table 4.2 Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Table 4.3 SMBus Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Table 5.1 SMBus Address Decode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Table 5.2 Protocol Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Table 5.3 Write Byte Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Table 5.4 Read Byte Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Table 5.5 Send Byte Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Table 5.6 Receive Byte Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Table 5.7 Alert Response Address Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Table 6.1 Supply Current vs. Conversion Rate for EMC1412 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Table 6.2 Temperature Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Table 7.1 Register Set in Hexadecimal Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Table 7.2 Temperature Data Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Table 7.3 Status Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Table 7.4 Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Table 7.5 Conversion Rate Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Table 7.6 Conversion Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Table 7.7 Temperature Limit Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Table 7.8 Scratchpad Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Table 7.9 One Shot Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Table 7.10 Therm Limit Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Table 7.11 Channel Mask Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Table 7.12 Consecutive ALERT Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Table 7.13 Consecutive Alert / Therm Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Table 7.14 Beta Configuration Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Table 7.15 CPU Beta Values. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Table 7.16 Ideality Configuration Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Table 7.17 Ideality Factor Look-Up Table (Diode Model) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Table 7.18 Substrate Diode Ideality Factor Look-Up Table (BJT Model) . . . . . . . . . . . . . . . . . . . . . . . . . 35 Table 7.19 Filter Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Table 7.20 FILTER Decode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Table 7.21 Product ID Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Table 7.22 Manufacturer ID Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Table 7.23 Revision Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Table 10.1 Customer Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 Revision 1.41 (02-23-12) 6 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Chapter 1 Block Diagram VDD EMC1412 Conversion Rate Register Switching Current Low Limit Registers Configuration Register SMBus Address Decode THERM / ADDR THERM Hysteresis Register SMDATA Internal Temperature Register Interupt Masking ALERT THERM Limit Register SMBus Interface Internal Temp Diode External Temperature Register(s) High Limit Registers Digital Mux ΔΣ ADC DN Digital Mux Analog Mux Limit Comparator SMCLK DP Status Registers GND Figure 1.1 EMC1412 Block Diagram Chapter 2 Delta 2.1 Functional Delta from EMC1412 rev A to rev B 1. Updated revision number to 04h. SMSC EMC1412 7 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Chapter 3 Pin Description VDD 1 8 SMCLK DP 2 7 SMDATA DN 3 6 ALERT THERM / ADDR 4 5 GND Figure 3.1 EMC1412 Pin Diagram, MSOP-8 VDD 1 DP 2 8 SMCLK 7 SMDATA Exposed pad DN 3 6 ALERT THERM / ADDR 4 5 GND Figure 3.2 EMC1412 Pin Diagram, TDFN-8 2mm x 3mm Table 3.1 EMC1412 Pin Description PIN NUMBER NAME 1 VDD 2 DP External diode positive (anode) connection AIO 3 DN External diode negative (cathode) connection AIO 4 Power supply TYPE Power THERM - Active low Critical THERM output signal - requires pull-up resistor OD (5V) ADDR - Selects SMBus address based on pullup resistor OD (5V) THERM / ADDR 5 GND 6 ALERT Revision 1.41 (02-23-12) FUNCTION Ground Power Active low digital ALERT output signal requires pull-up resistor 8 DATASHEET OD (5V) SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Table 3.1 EMC1412 Pin Description PIN NUMBER NAME FUNCTION 7 SMDATA SMBus Data input/output - requires pull-up resistor 8 SMCLK SMBus Clock input - requires pull-up resistor Bottom Pad Exposed Pad TYPE DIOD (5V) DI (5V) Not internally connected, but recommend grounding. - APPLICATION NOTE: For the 5V tolerant pins that have a pull-up resistor (SMCLK, SMDATA, THERM, and ALERT), the voltage difference between VDD and the pull-up voltage must never exceed 3.6V. The pin types are described Table 3.2. Table 3.2 Pin Types PIN TYPE Power AIO DI DESCRIPTION This pin is used to supply power or ground to the device. Analog Input / Output -This pin is used as an I/O for analog signals. Digital Input - This pin is used as a digital input. This pin is 5V tolerant. DIOD Digital Input / Open Drain Output - This pin is used as a digital I/O. When it is used as an output, it is open drain and requires a pull-up resistor. This pin is 5V tolerant. OD Open Drain Digital Output - This pin is used as a digital output. It is open drain and requires a pull-up resistor. This pin is 5V tolerant. SMSC EMC1412 9 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Chapter 4 Electrical Specifications 4.1 Absolute Maximum Ratings Table 4.1 Absolute Maximum Ratings DESCRIPTION RATING UNIT Supply Voltage (VDD) -0.3 to 4.0 V Voltage on 5V tolerant pins (V5VT_pin) -0.3 to 5.5 V 0 to 3.6 V -0.3 to VDD +0.3 V Operating Temperature Range -40 to +125 °C Storage Temperature Range -55 to +150 °C Voltage on 5V tolerant pins (|V5VT_pin - VDD|) (see Note 4.1) Voltage on any other pin to Ground Lead Temperature Range Refer to JEDEC Spec. J-STD-020 Package Thermal Characteristics for MSOP-8 Thermal Resistance (θj-a) 140.8 °C/W 89 °C/W 2000 V Package Thermal Characteristics for TDFN-8 Thermal Resistance (θj-a) ESD Rating, All pins HBM Note: Stresses at or above those listed could cause permanent damage to the device. This is a stress rating only and functional operation of the device at any other condition above those indicated in the operation sections of this specification is not implied. Note 4.1 Revision 1.41 (02-23-12) For the 5V tolerant pins that have a pull-up resistor (SMCLK, SMDATA, THERM, and ALERT), the pull-up voltage must not exceed 3.6V when the device is unpowered. 10 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet 4.2 Electrical Specifications Table 4.2 Electrical Specifications VDD = 3.0V to 3.6V, TA = -40°C to 125°C, all typical values at TA = 27°C unless otherwise noted. CHARACTERISTIC SYMBOL MIN TYP MAX UNITS CONDITIONS DC Power Supply Voltage VDD Supply Current IDD 3.0 3.3 3.6 V 430 850 µA 1 conversion / sec, dynamic averaging disabled 930 1200 µA 4 conversions / sec, dynamic averaging enabled µA > 16 conversions / sec, dynamic averaging enabled µA Device in Standby mode, no SMBus communications, ALERT and THERM pins not asserted. 1120 Standby Supply Current IDD 170 230 Internal Temperature Monitor Temperature Accuracy ±0.25 Temperature Resolution ±1 °C -5°C < TA < 100°C ±2 °C -40°C < TA < 125°C 0.125 °C External Temperature Monitor Temperature Accuracy Temperature Resolution ±0.25 ±1 °C +20°C < TDIODE < +110°C 0°C < TA < 100°C ±0.5 ±2 °C -40°C < TDIODE < 127°C 0.125 °C ms default settings nF Connected across external diode Conversion Time all Channels tCONV 190 Capacitive Filter CFILTER 2.2 2.7 ALERT and THERM pins Output Low Voltage VOL Leakage Current ILEAK SMSC EMC1412 0.4 ±5 11 DATASHEET V ISINK = 8mA µA ALERT and THERM pins Device powered or unpowered TA < 85°C pull-up voltage < 3.6V Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet 4.3 SMBus Electrical Characteristics Table 4.3 SMBus Electrical Specifications VDD = 3.0V to 3.6V, TA = -40°C to 125°C, all typical values are at TA = 27°C unless otherwise noted. CHARACTERISTIC SYMBOL MIN TYP MAX UNITS CONDITIONS SMBus Interface Input High Voltage VIH 2.0 VDD V 5V Tolerant Input Low Voltage VIL -0.3 0.8 V 5V Tolerant Leakage Current ILEAK ±5 µA Powered or unpowered TA < 85°C Hysteresis Input Capacitance CIN Output Low Sink Current IOL 420 mV 5 pF 8.2 15 mA SMDATA = 0.4V SMBus Timing 10 400 kHz 50 ns Clock Frequency fSMB Spike Suppression tSP Bus Free Time Stop to Start tBUF 1.3 µs Hold Time: Start tHD:STA 0.6 µs Setup Time: Start tSU:STA 0.6 µs Setup Time: Stop tSU:STO 0.6 µs Data Hold Time tHD:DAT 0 µs When transmitting to the master Data Hold Time tHD:DAT 0.3 µs When receiving from the master Data Setup Time tSU:DAT 100 ns Clock Low Period tLOW 1.3 µs Clock High Period tHIGH 0.6 µs Clock/Data Fall time tFALL 300 ns Min = 20+0.1CLOAD ns Clock/Data Rise time tRISE 300 ns Min = 20+0.1CLOAD ns Capacitive Load CLOAD 400 pF per bus line Revision 1.41 (02-23-12) 12 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Chapter 5 System Management Bus Interface Protocol 5.1 Communications Protocol The EMC1412 communicates with a host controller, such as an SMSC SIO, through the SMBus. The SMBus is a two-wire serial communication protocol between a computer host and its peripheral devices. A detailed timing diagram is shown in Figure 5.1. For the first 15ms after power-up the device may not respond to SMBus communications. . T HIGH T LOW T HD:STA T SU:STO T FALL SMCLK T RISE T HD:STA T HD:DAT T SU:DAT T SU:STA SMDATA T BUF S P S S - Start Condition P - Stop Condition P Figure 5.1 SMBus Timing Diagram 5.1.1 SMBus Start Bit The SMBus Start bit is defined as a transition of the SMBus Data line from a logic ‘1’ state to a logic ‘0’ state while the SMBus Clock line is in a logic ‘1’ state. 5.1.2 SMBus Address and RD / WR Bit The SMBus Address Byte consists of the 7-bit client address followed by the RD / WR indicator bit. If this RD / WR bit is a logic ‘0’, the SMBus Host is writing data to the client device. If this RD / WR bit is a logic ‘1’, the SMBus Host is reading data from the client device. The EMC1412-A SMBus slave address is determined by the pull-up resistor on the THERM pin as shown in Table 5.1, "SMBus Address Decode". The Address decode is performed by pulling known currents from VDD through the external resistor causing the pin voltage to drop based on the respective current / resistor relationship. This pin voltage is compared against a threshold that determines the value of the pull-up resistor. Table 5.1 SMBus Address Decode SMSC EMC1412 PULL UP RESISTOR ON THERM PIN (±5%) SMBUS ADDRESS 4.7k 1111_100(r/w)b 6.8k 1011_100(r/w)b 10k 1001_100(r/w)b 13 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Table 5.1 SMBus Address Decode (continued) PULL UP RESISTOR ON THERM PIN (±5%) SMBUS ADDRESS 15k 1101_100(r/w)b 22k 0011_100(r/w)b 33k 0111_100(r/w)b The EMC1412-1 SMBus address is hard coded to 1001_100(r/w). The EMC1412-2 SMBus address is hard coded to 1001_101(r/w). 5.1.3 THERM Pin Considerations Because of the decode method used to determine the SMBus Address, it is important that the pull-up resistance on the THERM pin be within the tolerances shown in Table 5.1. Additionally, the pull-up resistor on the THERM pin must be connected to the same 3.3V supply that drives the VDD pin. For 15ms after power up, the THERM pin must not be pulled low or the SMBus address will not be decoded properly. If the system requirements do not permit these conditions, the THERM pin must be isolated from its hard-wired OR’d bus during this time. One method of isolating this pin is shown in Figure 5.2. +3.3V +2.5 - 5V 22K VDD 1 8 SMCLK DP 2 7 SMDATA DN 3 6 ALERT THERM / ADDR 4 5 GND 4.7K – 33k EMC1412 Shared THERM Figure 5.2 Isolating THERM Pin 5.1.4 SMBus Data Bytes All SMBus Data bytes are sent most significant bit first and composed of 8-bits of information. 5.1.5 SMBus ACK and NACK Bits The SMBus client will acknowledge all data bytes that it receives. This is done by the client device pulling the SMBus data line low after the 8th bit of each byte that is transmitted. This applies to the Write Byte protocol. The Host will NACK (not acknowledge) the last data byte to be received from the client by holding the SMBus data line high after the 8th data bit has been sent. Revision 1.41 (02-23-12) 14 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet 5.1.6 SMBus Stop Bit The SMBus Stop bit is defined as a transition of the SMBus Data line from a logic ‘0’ state to a logic ‘1’ state while the SMBus clock line is in a logic ‘1’ state. When the device detects an SMBus Stop bit and it has been communicating with the SMBus protocol, it will reset its client interface and prepare to receive further communications. 5.1.7 SMBus Timeout The EMC1412 supports SMBus Timeout. If the clock line is held low for longer than 30ms, the device will reset its SMBus protocol. This function can be enabled by setting the TIMEOUT bit in the Consecutive Alert Register (see Section 7.11). 5.1.8 SMBus and I2C Compatibility The EMC1412 is compatible with SMBus and I2C. The major differences between SMBus and I2C devices are highlighted here. For more information, refer to the SMBus 2.0 and I2C specifications. For information on using the EMC1412 in an I2C system, refer to SMSC AN 14.0 SMSC Dedicated Slave Devices in I2C Systems. 1. EMC1412 supports I2C fast mode at 400kHz. This covers the SMBus max time of 100kHz. 2. Minimum frequency for SMBus communications is 10kHz. 3. The SMBus client protocol will reset if the clock is held at a logic ‘0’ for longer than 30ms. This timeout functionality is disabled by default in the EMC1412 and can be enabled by writing to the TIMEOUT bit. I2C does not have a timeout. 4. I2C devices do not support the Alert Response Address functionality (which is optional for SMBus). Attempting to communicate with the EMC1412 SMBus interface with an invalid slave address or invalid protocol will result in no response from the device and will not affect its register contents. Stretching of the SMCLK signal is supported, provided other devices on the SMBus control the timing. 5.2 SMBus Protocols The device supports Send Byte, Read Byte, Write Byte, Receive Byte, and the Alert Response Address as valid protocols as shown below. All of the below protocols use the convention in Table 5.2. Table 5.2 Protocol Format 5.2.1 DATA SENT TO DEVICE DATA SENT TO THE HOST # of bits sent # of bits sent Write Byte The Write Byte is used to write one byte of data to the registers, as shown in Table 5.3. Table 5.3 Write Byte Protocol START SLAVE ADDRESS WR ACK REGISTER ADDRESS ACK REGISTER DATA ACK STOP 1 -> 0 YYYY_YYY 0 0 XXh 0 XXh 0 0 -> 1 SMSC EMC1412 15 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet 5.2.2 Read Byte The Read Byte protocol is used to read one byte of data from the registers as shown in Table 5.4. Table 5.4 Read Byte Protocol START SLAVE ADDRESS WR ACK REGISTER ADDRESS ACK START SLAVE ADDRESS RD ACK REGISTER DATA NACK STOP 1 -> 0 YYYY_ YYY 0 0 XXh 0 1 -> 0 YYYY_ YYY 1 0 XX 1 0 -> 1 5.2.3 Send Byte The Send Byte protocol is used to set the internal address register pointer to the correct address location. No data is transferred during the Send Byte protocol as shown in Table 5.5. Table 5.5 Send Byte Protocol START SLAVE ADDRESS WR ACK REGISTER ADDRESS ACK STOP 1 -> 0 YYYY_YYY 0 0 XXh 0 0 -> 1 5.2.4 Receive Byte The Receive Byte protocol is used to read data from a register when the internal register address pointer is known to be at the right location (e.g. set via Send Byte). This is used for consecutive reads of the same register as shown in Table 5.6. Table 5.6 Receive Byte Protocol START SLAVE ADDRESS RD ACK REGISTER DATA NACK STOP 1 -> 0 YYYY_YYY 1 0 XXh 1 0 -> 1 5.3 Alert Response Address The ALERT output can be used as a processor interrupt or as an SMBus Alert. When it detects that the ALERT pin is asserted, the host will send the Alert Response Address (ARA) to the general address of 0001_100xb. All devices with active interrupts will respond with their client address as shown in Table 5.7. Table 5.7 Alert Response Address Protocol START ALERT RESPONSE ADDRESS RD ACK DEVICE ADDRESS NACK STOP 1 -> 0 0001_100 1 0 YYYY_YYY 1 0 -> 1 Revision 1.41 (02-23-12) 16 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet The EMC1412 will respond to the ARA in the following way: 1. Send Slave Address and verify that full slave address was sent (i.e. the SMBus communication from the device was not prematurely stopped due to a bus contention event). 2. Set the MASK bit to clear the ALERT pin. APPLICATION NOTE: The ARA does not clear the Status Register and if the MASK bit is cleared prior to the Status Register being cleared, the ALERT pin will be reasserted. SMSC EMC1412 17 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Chapter 6 Product Description The EMC1412 is an SMBus temperature sensor. The EMC1412 monitors one internal diode and one externally connected temperature diode. Thermal management is performed in cooperation with a host device. This consists of the host reading the temperature data of both the external and internal temperature diodes of the EMC1412 and using that data to control the speed of one or more fans. The EMC1412 has two levels of monitoring. The first provides a maskable ALERT signal to the host when the measured temperatures exceeds user programmable limits. This allows the EMC1412 to be used as an independent thermal watchdog to warn the host of temperature hot spots without direct control by the host. The second level of monitoring provides a non maskable interrupt on the THERM pin if the measured temperatures meet or exceed a second programmable limit. Figure 6.1 shows a system level block diagram of the EMC1412. VDD = 3.3V 3.3V – 5V VDD CPU / GPU Host DP Thermal Junction DN SMCLK EMC1412 SMDATA ALERT SMBus Interface THERM / ADDR GND Power Control Figure 6.1 System Diagram for EMC1412 6.1 Modes of Operation The EMC1412 has two modes of operation. 6.1.1 Active (Run) - In this mode of operation, the ADC is converting on all temperature channels at the programmed conversion rate. The temperature data is updated at the end of every conversion and the limits are checked. In Active mode, writing to the one-shot register will do nothing. Standby (Stop) - In this mode of operation, the majority of circuitry is powered down to reduce supply current. The temperature data is not updated and the limits are not checked. In this mode of operation, the SMBus is fully active and the part will return requested data. Writing to the oneshot register will enable the device to update all temperature channels. Once all the channels are updated, the device will return to the Standby mode. Conversion Rates The EMC1412 may be configured for different conversion rates based on the system requirements. The conversion rate is configured as described in Section 7.5. The default conversion rate is 4 conversions per second. Other available conversion rates are shown in Table 7.6, "Conversion Rate". Revision 1.41 (02-23-12) 18 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet 6.1.2 Dynamic Averaging Dynamic averaging causes the EMC1412 to measure the external diode channels for an extended time based on the selected conversion rate. This functionality can be disabled for increased power savings at the lower conversion rates (see Section 7.4, "Configuration Register"). When dynamic averaging is enabled, the device will automatically adjust the sampling and measurement time for the external diode channels. This allows the device to average 2x or 16x longer than the normal 11 bit operation (nominally 21ms per channel) while still maintaining the selected conversion rate. The benefits of dynamic averaging are improved noise rejection due to the longer integration time as well as less random variation of the temperature measurement. When enabled, the dynamic averaging applies when a one-shot command is issued. The device will perform the desired averaging during the one-shot operation according to the selected conversion rate. When enabled, the dynamic averaging will affect the average supply current based on the chosen conversion rate as shown in Table 6.1. Table 6.1 Supply Current vs. Conversion Rate for EMC1412 AVERAGE SUPPLY CURRENT AVERAGING FACTOR (BASED ON 11-BIT OPERATION) CONVERSION RATE ENABLED (DEFAULT) DISABLED ENABLED (DEFAULT) DISABLED 1 / 16 sec 660uA 430uA 16x 1x 1 / 8 sec 660uA 430uA 16x 1x 1 / 4 sec 660uA 430uA 16x 1x 1 / 2 sec 660uA 430uA 16x 1x 1 / sec 660uA 430uA 16x 1x 2 / sec 930uA 475uA 16x 1x 4 / sec (default) 950uA 510uA 8x 1x 8 / sec 1010uA 630uA 4x 1x 16 / sec 1020uA 775uA 2x 1x 32 / sec 1050uA 1050uA 1x 1x 64 / sec 1100uA 1100uA 0.5x 0.5x 6.2 THERM Output The THERM output is asserted independently of the ALERT output and cannot be masked. Whenever any of the measured temperatures exceed the user programmed Therm Limit values for the programmed number of consecutive measurements, the THERM output is asserted. Once it has been asserted, it will remain asserted until all measured temperatures drop below the Therm Limit minus the Therm Hysteresis (also programmable). When the THERM pin is asserted, the THERM status bits will likewise be set. Reading these bits will not clear them until the THERM pin is deasserted. Once the THERM pin is deasserted, the THERM status bits will be automatically cleared. SMSC EMC1412 19 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet 6.3 ALERT Output The ALERT pin is an open drain output and requires a pull-up resistor to VDD and has two modes of operation: interrupt mode and comparator mode. The mode of the ALERT output is selected via the ALERT / COMP bit in the Configuration Register (see Section 7.4). 6.3.1 ALERT Pin Interrupt Mode When configured to operate in interrupt mode, the ALERT pin asserts low when an out of limit measurement (> high limit or < low limit) is detected on any diode or when a diode fault is detected. The ALERT pin will remain asserted as long as an out-of-limit condition remains. Once the out-of-limit condition has been removed, the ALERT pin will remain asserted until the appropriate status bits are cleared. The ALERT pin can be masked by setting the MASK_ALL bit. Once the ALERT pin has been masked, it will be de-asserted and remain de-asserted until the MASK_ALL bit is cleared by the user. Any interrupt conditions that occur while the ALERT pin is masked will update the Status Register normally. There are also individual channel masks (see Section 7.10). The ALERT pin is used as an interrupt signal or as an SMBus Alert signal that allows an SMBus slave to communicate an error condition to the master. One or more ALERT outputs can be hard-wired together. 6.3.2 ALERT Pin Comparator Mode When the ALERT pin is configured to operate in comparator mode, it will be asserted if any of the measured temperatures exceeds the respective high limit. The ALERT pin will remain asserted until all temperatures drop below the corresponding high limit minus the Therm Hysteresis value. When the ALERT pin is asserted in comparator mode, the corresponding high limit status bits will be set. Reading these bits will not clear them until the ALERT pin is deasserted. Once the ALERT pin is deasserted, the status bits will be automatically cleared. The MASK_ALL bit will not block the ALERT pin in this mode; however, the individual channel masks (see Section 7.10) will prevent the respective channel from asserting the ALERT pin. 6.4 Temperature Measurement The EMC1412 can monitor the temperature of one externally connected diode. The external diode channel is configured with Resistance Error Correction and Beta Compensation based on user settings and system requirements. The device contains programmable High, Low, and Therm limits for all measured temperature channels. If the measured temperature goes below the Low limit or above the High limit, the ALERT pin can be asserted (based on user settings). If the measured temperature meets or exceeds the Therm Limit, the THERM pin is asserted unconditionally, providing two tiers of temperature detection. 6.4.1 Beta Compensation The EMC1412 is configured to monitor the temperature of basic diodes (e.g., 2N3904) or CPU thermal diodes. It automatically detects the type of external diode (CPU diode or diode connected transistor) and determines the optimal setting to reduce temperature errors introduced by beta variation. Compensating for this error is also known as implementing the transistor or BJT model for temperature measurement. For discrete transistors configured with the collector and base shorted together, the beta is generally sufficiently high such that the percent change in beta variation is very small. For example, a 10% variation in beta for two forced emitter currents with a transistor whose ideal beta is 50 would contribute approximately 0.25°C error at 100°C. However for substrate transistors where the base-emitter junction is used for temperature measurement and the collector is tied to the substrate, the proportional beta variation will cause large error. For example, a 10% variation in beta for two forced emitter currents with a transistor whose ideal beta is 0.5 would contribute approximately 8.25°C error at 100°C. Revision 1.41 (02-23-12) 20 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet 6.4.2 Resistance Error Correction (REC) Parasitic resistance in series with the external diodes will limit the accuracy obtainable from temperature measurement devices. The voltage developed across this resistance by the switching diode currents cause the temperature measurement to read higher than the true temperature. Contributors to series resistance are PCB trace resistance, on die (i.e. on the processor) metal resistance, bulk resistance in the base and emitter of the temperature transistor. Typically, the error caused by series resistance is +0.7°C per ohm. The EMC1412 automatically corrects up to 100 ohms of series resistance. 6.4.3 Programmable External Diode Ideality Factor The EMC1412 is designed for external diodes with an ideality factor of 1.008. Not all external diodes, processor or discrete, will have this exact value. This variation of the ideality factor introduces error in the temperature measurement which must be corrected for. This correction is typically done using programmable offset registers. Since an ideality factor mismatch introduces an error that is a function of temperature, this correction is only accurate within a small range of temperatures. To provide maximum flexibility to the user, the EMC1412 provides a 6-bit register for each external diode where the ideality factor of the diode used is programmed to eliminate errors across all temperatures. APPLICATION NOTE: When monitoring a substrate transistor or CPU diode and beta compensation is enabled, the Ideality Factor should not be adjusted. Beta Compensation automatically corrects for most ideality errors. 6.5 Diode Faults The EMC1412 detects an open on the DP and DN pins, and a short across the DP and DN pins. For each temperature measurement made, the device checks for a diode fault on the external diode channel(s). When a diode fault is detected, the ALERT pin asserts (unless masked, see Section 6.6) and the temperature data reads 00h in the MSB and LSB registers (note: the low limit will not be checked). A diode fault is defined as one of the following: an open between DP and DN, a short from VDD to DP, or a short from VDD to DN. If a short occurs across DP and DN or a short occurs from DP to GND, the low limit status bit is set and the ALERT pin asserts (unless masked). This condition is indistinguishable from a temperature measurement of 0.000°C (-64°C in extended range) resulting in temperature data of 00h in the MSB and LSB registers. If a short from DN to GND occurs (with a diode connected), temperature measurements will continue as normal with no alerts. 6.6 Consecutive Alerts The EMC1412 contain multiple consecutive alert counters. One set of counters applies to the ALERT pin and the second set of counters applies to the THERM pin. Each temperature measurement channel has a separate consecutive alert counter for each of the ALERT and THERM pins. All counters are user programmable and determine the number of consecutive measurements that a temperature channel(s) must be out-of-limit or reporting a diode fault before the corresponding pin is asserted. See Section 7.11, "Consecutive ALERT Register" for more details on the consecutive alert function. 6.7 Digital Filter To reduce the effect of noise and temperature spikes on the reported temperature, the External Diode channel uses a programmable digital filter. This filter can be configured as Level 1, Level 2, or Disabled (default) (see Section 7.14). The typical filter performance is shown in Figure 6.2 and Figure 6.3. SMSC EMC1412 21 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Filter Step Response Temperature (C) 90 Disabled 80 70 Level1 Level2 60 50 40 30 20 10 0 0 2 4 6 8 10 12 14 Samples Figure 6.2 Temperature Filter Step Response Filter Impulse Response 90 Temperature (C) 80 Disabled 70 60 50 Level1 40 Level2 30 20 10 0 0 2 4 6 8 10 12 14 Samples Figure 6.3 Temperature Filter Impulse Response Revision 1.41 (02-23-12) 22 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet 6.8 Temperature Measurement Results and Data The temperature measurement results are stored in the internal and external temperature registers. These are then compared with the values stored in the high and low limit registers. Both external and internal temperature measurements are stored in 11-bit format with the eight (8) most significant bits stored in a high byte register and the three (3) least significant bits stored in the three (3) MSB positions of the low byte register. All other bits of the low byte register are set to zero. The EMC1412 has two selectable temperature ranges. The default range is from 0°C to +127°C and the temperature is represented as binary number able to report a temperature from 0°C to +127.875°C in 0.125°C steps. The extended range is an extended temperature range from -64°C to +191°C. The data format is a binary number offset by 64°C. The extended range is used to measure temperature diodes with a large known offset (such as AMD processor diodes) where the diode temperature plus the offset would be equivalent to a temperature higher than +127°C. Table 6.2 shows the default and extended range formats. Table 6.2 Temperature Data Format TEMPERATURE (°C) DEFAULT RANGE 0°C TO 127°C EXTENDED RANGE -64°C TO 191°C Diode Fault 000 0000 0000 000 0000 0000 -64 000 0000 0000 000 0000 0000 Note 6.2 -1 000 0000 0000 001 1111 1000 0 000 0000 0000 Note 6.1 010 0000 0000 0.125 000 0000 0001 010 0000 0001 1 000 0000 1000 010 0000 1000 64 010 0000 0000 100 0000 0000 65 010 0000 1000 100 0000 1000 127 011 1111 1000 101 1111 1000 127.875 011 1111 1111 101 1111 1111 128 011 1111 1111 Note 6.3 110 0000 0000 190 011 1111 1111 111 1111 0000 191 011 1111 1111 111 1111 1000 >= 191.875 011 1111 1111 111 1111 1111 Note 6.4 Note 6.1 In default mode, all temperatures < 0°C will be reported as 0°C. Note 6.2 In the extended range, all temperatures < -64°C will be reported as -64°C. Note 6.3 For the default range, all temperatures > +127.875°C will be reported as +127.875°C. Note 6.4 For the extended range, all temperatures > +191.875°C will be reported as +191.875°C. SMSC EMC1412 23 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet 6.9 External Diode Connections The EMC1412 can be configured to measure a CPU substrate transistor, a discrete 2N3904 thermal diode, or an AMD processor diode. The diodes can be connected as indicated in Figure 6.4. to DP1 to DP1 to DN1 to DN1 Local Ground Typical remote substrate transistor e.g. CPU substrate PNP Typical remote discrete NPN transistor e.g. 2N3904 Figure 6.4 Diode Configurations Revision 1.41 (02-23-12) 24 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Chapter 7 Register Description The registers shown in Table 7.1 are accessible through the SMBus. An entry of ‘-’ indicates that the bit is not used and will always read ‘0’. Table 7.1 Register Set in Hexadecimal Order REGISTER ADDRESS R/W REGISTER NAME FUNCTION DEFAULT VALUE 00h R Internal Diode Data High Byte Stores the integer data for the Internal Diode 01h R External Diode Data High Byte Stores the integer data for the External Diode 00h 02h R-C Status Stores status bits for the Internal Diode and External Diode 00h Page 27 03h R/W Configuration Controls the general operation of the device (mirrored at address 09h) 00h Page 28 04h R/W Conversion Rate Controls the conversion rate for updating temperature data (mirrored at address 0Ah) 06h (4/sec) Page 29 05h R/W Internal Diode High Limit Stores the 8-bit high limit for the Internal Diode (mirrored at address 0Bh) 55h (85°C) 06h R/W Internal Diode Low Limit Stores the 8-bit low limit for the Internal Diode (mirrored at address 0Ch) 00h (0°C) 55h (85°C) PAGE 00h Page 27 Page 30 07h R/W External Diode High Limit High Byte Stores the integer portion of the high limit for the External Diode (mirrored at register 0Dh) 08h R/W External Diode Low Limit High Byte Stores the integer portion of the low limit for the External Diode (mirrored at register 0Eh) 00h (0°C) 09h R/W Configuration Controls the general operation of the device (mirrored at address 03h) 00h Page 28 0Ah R/W Conversion Rate Controls the conversion rate for updating temperature data (mirrored at address 04h) 06h (4/sec) Page 29 SMSC EMC1412 25 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Table 7.1 Register Set in Hexadecimal Order (continued) REGISTER ADDRESS R/W REGISTER NAME FUNCTION DEFAULT VALUE 0Bh R/W Internal Diode High Limit Stores the 8-bit high limit for the Internal Diode (mirrored at address 05h) 55h (85°C) 0Ch R/W Internal Diode Low Limit Stores the 8-bit low limit for the Internal Diode (mirrored at address 06h) 00h (0°C) 55h (85°C) PAGE Page 30 0Dh R/W External Diode High Limit High Byte Stores the integer portion of the high limit for the External Diode (mirrored at register 07h) 0Eh R/W External Diode Low Limit High Byte Stores the integer portion of the low limit for the External Diode (mirrored at register 08h) 00h (0°C) 0Fh W One shot A write to this register initiates a one shot update. 00h Page 31 10h R External Diode Data Low Byte Stores the fractional data for the External Diode 00h Page 27 11h R/W Scratchpad Scratchpad register for software compatibility 00h Page 30 12h R/W Scratchpad Scratchpad register for software compatibility 00h Page 30 13h R/W External Diode High Limit Low Byte Stores the fractional portion of the high limit for the External Diode 00h 14h R/W External Diode Low Limit Low Byte Stores the fractional portion of the low limit for the External Diode 00h 19h R/W External Diode Therm Limit Stores the 8-bit critical temperature limit for the External Diode 55h (85°C) Page 31 1Fh R/W Channel Mask Register Controls the masking of individual channels 00h Page 31 20h R/W Internal Diode Therm Limit Stores the 8-bit critical temperature limit for the Internal Diode 55h (85°C) 21h R/W Therm Hysteresis Stores the 8-bit hysteresis value that applies to all Therm limits 0Ah (10°C) 22h R/W Consecutive ALERT Controls the number of out-of-limit conditions that must occur before an interrupt is asserted 70h Page 32 25h R/W External Diode Beta Configuration Stores the Beta Compensation circuitry settings for External Diode 08h Page 33 27h R/W External Diode Ideality Factor Stores the ideality factor for the External Diode 12h (1.008) Page 34 29h R Internal Diode Data Low Byte Stores the fractional data for the Internal Diode 00h Page 27 40h R/W Filter Control Controls the digital filter setting for the External Diode channel 00h Page 36 Page 30 Page 31 Revision 1.41 (02-23-12) 26 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Table 7.1 Register Set in Hexadecimal Order (continued) REGISTER ADDRESS R/W REGISTER NAME FUNCTION FDh R Product ID FEh R FFh R 7.1 DEFAULT VALUE PAGE Stores a fixed value that identifies the device 20h Page 36 Manufacturer ID Stores a fixed value that represents SMSC 5Dh Page 36 Revision Stores a fixed value that represents the revision number 04h Page 37 Data Read Interlock When any temperature channel high byte register is read, the corresponding low byte is copied into an internal ‘shadow’ register. The user is free to read the low byte at any time and be guaranteed that it will correspond to the previously read high byte. Regardless if the low byte is read or not, reading from the same high byte register again will automatically refresh this stored low byte data. 7.2 Temperature Data Registers Table 7.2 Temperature Data Registers ADDR R/W REGISTER B7 B6 B5 B4 B3 B2 B1 B0 DEFAULT 00h R Internal Diode High Byte 128 64 32 16 8 4 2 1 00h 29h R Internal Diode Low Byte 0.5 0.25 0.125 - - - - - 00h 01h R External Diode High Byte 128 64 32 16 8 4 2 1 00h 10h R External Diode Low Byte 0.5 0.25 0.125 - - - - - 00h As shown in Table 7.2, all temperatures are stored as an 11-bit value with the high byte representing the integer value and the low byte representing the fractional value left justified to occupy the MSBits. 7.3 Status Register Table 7.3 Status Register ADDR R/W REGISTER B7 B6 B5 B4 B3 B2 B1 B0 DEFAULT 02h R-C Status BUSY IHIGH ILOW EHIGH ELOW FAULT ETHERM ITHERM 00h The Status Register reports the operating status of the Internal Diode and External Diode channels. When any of the bits are set (excluding the BUSY bit) either the ALERT or THERM pin is being asserted. The ALERT and THERM pins are controlled by the respective consecutive alert counters (see Section 7.11) and will not be asserted until the programmed consecutive alert count has been reached. SMSC EMC1412 27 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet The status bits (except E1THERM and ITHERM) will remain set until read unless the ALERT pin is configured as a second THERM output (see Section 6.3.2). Bit 7 - BUSY - This bit indicates that the ADC is currently converting. This bit does not cause either the ALERT or THERM pins to be asserted. Bit 6 - IHIGH - This bit is set when the Internal Diode channel exceeds its programmed high limit. When set, this bit will assert the ALERT pin. Bit 5 - ILOW - This bit is set when the Internal Diode channel drops below its programmed low limit. When set, this bit will assert the ALERT pin. Bit 4 - EHIGH - This bit is set when the External Diode channel exceeds its programmed high limit. When set, this bit will assert the ALERT pin. Bit 3 - ELOW - This bit is set when the External Diode channel drops below its programmed low limit. When set, this bit will assert the ALERT pin. Bit 2 - FAULT - This bit is asserted when a diode fault is detected. When set, this bit will assert the ALERT pin. Bit 1 - ETHERM - This bit is set when the External Diode channel exceeds the programmed Therm Limit. When set, this bit will assert the THERM pin. This bit will remain set until the THERM pin is released at which point it will be automatically cleared. Bit 0 - ITHERM - This bit is set when the Internal Diode channel exceeds the programmed Therm Limit. When set, this bit will assert the THERM pin. This bit will remain set until the THERM pin is released at which point it will be automatically cleared. 7.4 Configuration Register Table 7.4 Configuration Register ADDR R/W REGISTER B7 B6 B5 B4 B3 B2 B1 B0 DEFAULT R/W Configuration MASK_ ALL RUN/ STOP ALERT/ COMP RECD - RANGE DAVG_ DIS - 00h 03h 09h The Configuration Register controls the basic operation of the device. This register is fully accessible at either address. Bit 7 - MASK_ALL - Masks the ALERT pin from asserting. ‘0’ - (default) - The ALERT pin is not masked. If any of the appropriate status bits are set the ALERT pin will be asserted. ‘1’ - - The ALERT pin is masked. It will not be asserted for any interrupt condition unless it is configured in comparator mode. The Status Register will be updated normally. Bit 6 - RUN / STOP - Controls Active/Standby modes. ‘0’ (default) - The device is in Active mode and converting on all channels. ‘1’ - The device is in Standby mode and not converting. Bit 5 - ALERT/COMP - Controls the operation of the ALERT pin. ‘0’ (default) - The ALERT pin acts as described in Section 6.3. ‘1’ - The ALERT pin acts in comparator mode as described in Section 6.3.2. In this mode the MASK_ALL bit is ignored. Bit 4 - RECD - Disables the Resistance Error Correction (REC) for the External Diode. ‘0’ (default) - REC is enabled for the External Diode. ‘1’ - REC is disabled for the External Diode. Revision 1.41 (02-23-12) 28 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Bit 2 - RANGE - Configures the measurement range and data format of the temperature channels. ‘0’ (default) - The temperature measurement range is 0°C to +127.875°C and the data format is binary. ‘1’ -The temperature measurement range is -64°C to +191.875°C and the data format is offset binary (see Table 6.2). Bit 1 - DAVG_DIS - Disables the dynamic averaging feature on all temperature channels. 7.5 ‘0’ (default) - The dynamic averaging feature is enabled. All temperature channels will be converted with an averaging factor that is based on the conversion rate as shown in Table 6.1. ‘1’ - The dynamic averaging feature is disabled. All temperature channels will be converted with a maximum averaging factor of 1x (equivalent to 11-bit conversion). For higher conversion rates, this averaging factor will be reduced as shown in Table 6.1. Conversion Rate Register Table 7.5 Conversion Rate Register ADDR R/W REGISTER B7 B6 B5 B4 R/W Conversion Rate - - - - 04h 0Ah B3 B2 B1 B0 DEFAULT 06h (4/sec) CONV[3:0] The Conversion Rate Register controls how often the temperature measurement channels are updated and compared against the limits. This register is fully accessible at either address. Bits 3-0 - CONV[3:0] - Determines the conversion rate as shown in Table 7.6. Table 7.6 Conversion Rate CONV[3:0] HEX 3 2 1 0 CONVERSIONS / SECOND 0h 0 0 0 0 1 / 16 1h 0 0 0 1 1/8 2h 0 0 1 0 1/4 3h 0 0 1 1 1/2 4h 0 1 0 0 1 5h 0 1 0 1 2 6h 0 1 1 0 4 (default) 7h 0 1 1 1 8 8h 1 0 0 0 16 9h 1 0 0 1 32 Ah 1 0 1 0 64 Bh - Fh SMSC EMC1412 All others 1 29 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet 7.6 Limit Registers Table 7.7 Temperature Limit Registers ADDR. R/W REGISTER B7 B6 B5 B4 B3 B2 B1 B0 DEFAULT R/W Internal Diode High Limit 128 64 32 16 8 4 2 1 55h (85°C) R/W Internal Diode Low Limit 128 64 32 16 8 4 2 1 00h (0°C) R/W External Diode High Limit High Byte 128 64 32 16 8 4 2 1 55h (85°C) R/W External Diode High Limit Low Byte 0.5 0.25 0.125 - - - - - 00h R/W External Diode Low Limit High Byte 128 64 32 16 8 4 2 1 00h (0°C) R/W External Diode Low Limit Low Byte 0.5 0.25 0.125 - - - - - 00h 05h 0Bh 06h 0Ch 07h 0Dh 13h 08h 0Eh 14h The device contains both high and low limits for all temperature channels. If the measured temperature exceeds the high limit, then the corresponding status bit is set and the ALERT pin is asserted. Likewise, if the measured temperature is less than or equal to the low limit, the corresponding status bit is set and the ALERT pin is asserted. The data format for the limits must match the selected data format for the temperature so that if the extended temperature range is used, the limits must be programmed in the extended data format. The limit registers with multiple addresses are fully accessible at either address. When the device is in Standby mode, updating the limit registers will have no effect until the next conversion cycle occurs. This can be initiated via a write to the One Shot Register or by clearing the RUN / STOP bit in the Configuration Register (see Section 7.4). 7.7 Scratchpad Registers Table 7.8 Scratchpad Register ADDR R/W REGISTER B7 B6 B5 B4 B3 B2 B1 B0 DEFAULT 11h R/W Scratchpad 7 6 5 4 3 2 1 0 00h 12h R/W Scratchpad 7 6 5 4 3 2 1 0 00h The Scratchpad Registers are Read / Write registers that are used for place holders to be software compatible with legacy programs. Reading from the registers will return what is written to them. Revision 1.41 (02-23-12) 30 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet 7.8 One Shot Register Table 7.9 One Shot Register ADDR. R/W REGISTER 0Fh W One Shot B7 B6 B5 B4 B3 B2 B1 B0 Writing to this register initiates a single conversion cycle. Data is not stored and always reads 00h DEFAULT 00h The One Shot Register is used to initiate a one shot command. Writing to the one shot register when the device is in standby mode and BUSY bit (in Status Register) is ‘0’, will immediately cause the ADC to update all temperature measurements. Writing to the One Shot Register while the device is in active mode will have no effect. 7.9 Therm Limit Registers Table 7.10 Therm Limit Registers ADDR. R/W REGISTER B7 B6 B5 B4 B3 B2 B1 B0 DEFAULT 19h R/W External Diode Therm Limit 128 64 32 16 8 4 2 1 55h (85°C) 20h R/W Internal Diode Therm Limit 128 64 32 16 8 4 2 1 55h (85°C) 21h R/W Therm Hysteresis 128 64 32 16 8 4 2 1 0Ah (10°C) The Therm Limit Registers are used to determine whether a critical thermal event has occurred. If the measured temperature exceeds the Therm Limit, the THERM pin is asserted. The limit setting must match the chosen data format of the temperature reading registers. Unlike the ALERT pin, the THERM pin cannot be masked. Additionally, the THERM pin will be released once the temperature drops below the corresponding threshold minus the Therm Hysteresis. 7.10 Channel Mask Register Table 7.11 Channel Mask Register ADDR. R/W REGISTER B7 B6 B5 B4 B3 B2 B1 B0 DEFAULT 1Fh R/W Channel Mask - - - - - - E MASK INT MASK 00h The Channel Mask Register controls individual channel masking. When a channel is masked, the ALERT pin will not be asserted when the masked channel reads a diode fault or out of limit error. The channel mask does not mask the THERM pin. Bit 1 - EMASK - Masks the ALERT pin from asserting when the External Diode channel is out of limit or reports a diode fault. SMSC EMC1412 ‘0’ (default) - The External Diode channel will cause the ALERT pin to be asserted if it is out of limit or reports a diode fault. 31 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet ‘1’ - The External Diode channel will not cause the ALERT pin to be asserted if it is out of limit or reports a diode fault. Bit 0 - INTMASK - Masks the ALERT pin from asserting when the Internal Diode temperature is out of limit. 7.11 ‘0’ (default) - The Internal Diode channel will cause the ALERT pin to be asserted if it is out of limit. ‘1’ - The Internal Diode channel will not cause the ALERT pin to be asserted if it is out of limit. Consecutive ALERT Register Table 7.12 Consecutive ALERT Register ADDR. R/W REGISTER B7 22h R/W Consecutive ALERT TIME OUT B6 B5 B4 CTHRM[2:0] B3 B2 B1 CALRT[2:0] B0 DEFAULT - 70h The Consecutive ALERT Register determines how many times an out-of-limit error or diode fault must be detected in consecutive measurements before the ALERT or THERM pin is asserted. Additionally, the Consecutive ALERT Register controls the SMBus Timeout functionality. An out-of-limit condition (i.e. HIGH, LOW, or FAULT) occurring on the same temperature channel in consecutive measurements will increment the consecutive alert counter. The counters will also be reset if no out-of-limit condition or diode fault condition occurs in a consecutive reading. When the ALERT pin is configured as an interrupt, when the consecutive alert counter reaches its programmed value, the following will occur: the STATUS bit(s) for that channel and the last error condition(s) (i.e. EHIGH) will be set to ‘1’, the ALERT pin will be asserted, the consecutive alert counter will be cleared, and measurements will continue. When the ALERT pin is configured as a comparator, the consecutive alert counter will ignore diode fault and low limit errors and only increment if the measured temperature exceeds the High Limit. Additionally, once the consecutive alert counter reaches the programmed limit, the ALERT pin will be asserted, but the counter will not be reset. It will remain set until the temperature drops below the High Limit minus the Therm Hysteresis value. For example, if the CALRT[2:0] bits are set for 4 consecutive alerts on an EMC1412 device, the high limits are set at 70°C, and none of the channels are masked, then the ALERT pin will be asserted after the following four measurements: 1. Internal Diode reads 71°C and the external diode reads 69°C. Consecutive alert counter for INT is incremented to 1. 2. Both the Internal Diode and the External Diode read 71°C. Consecutive alert counter for INT is incremented to 2 and for EXT is set to 1. 3. The External Diode reads 71°C and the Internal Diode read 69°C. Consecutive alert counter for INT is cleared and EXT is incremented to 2. 4. The Internal Diode reads 71°C and the external diode reads 71°C. Consecutive alert counter for INT is set to 1 and EXT is incremented to 3. 5. The Internal Diode reads 71°C and the external diode reads 71°C. Consecutive alert counter for INT is incremented to 2 and EXT is incremented to 4. The appropriate status bits are set for EXT and the ALERT pin is asserted. EXT counter is reset to 0 and all other counters hold the last value until the next temperature measurement. Bit 7 - TIMEOUT - Determines whether the SMBus Timeout function is enabled. ‘0’ (default) - The SMBus Timeout feature is disabled. The SMCLK line can be held low indefinitely without the device resetting its SMBus protocol. Revision 1.41 (02-23-12) 32 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet ‘1’ - The SMBus Timeout feature is enabled. If the SMCLK line is held low for more than 30ms, the device will reset the SMBus protocol. Bits 6-4 - CTHRM[2:0] - Determines the number of consecutive measurements that must exceed the corresponding Therm Limit before the THERM pin is asserted. All temperature channels use this value to set the respective counters. The consecutive Therm counter is incremented whenever any measurement exceed the corresponding Therm Limit. If the temperature drops below the Therm Limit, the counter is reset. If a number of consecutive measurements above the Therm Limit occurs, the THERM pin is asserted low. Once the THERM pin has been asserted, the consecutive therm counter will not reset until the corresponding temperature drops below the Therm Limit minus the Therm Hysteresis value. The bits are decoded as shown in Table 7.13. The default setting is 4 consecutive out of limit conversions. Bits 3-1 - CALRT[2:0] - Determine the number of consecutive measurements that must have an out of limit condition or diode fault before the ALERT pin is asserted. All temperature channels use this value to set the respective counters. The bits are decoded as shown in Table 7.13. The default setting is 1 consecutive out of limit conversion. Table 7.13 Consecutive Alert / Therm Settings 7.12 NUMBER OF CONSECUTIVE OUT OF LIMIT MEASUREMENTS 2 1 0 0 0 0 1 (default for CALRT[2:0]) 0 0 1 2 0 1 1 3 1 1 1 4 (default for CTHRM[2:0]) Beta Configuration Register Table 7.14 Beta Configuration Register ADDR. R/W REGISTER B7 B6 B5 B4 B3 25h R/W External Diode Beta Configuration - - - - ENABLE B2 B1 B0 BETA[2:0] DEFAULT 08h This register is used to set the Beta Compensation factor that is used for the external diode channel. Bit 3 - ENABLE - Enables the Beta Compensation factor auto-detection function. ‘0’ - The Beta Compensation Factor auto-detection circuitry is disabled. ‘1’ (default) - The Beta Compensation factor auto-detection circuitry is enabled. At the beginning of every conversion, the optimal Beta Compensation factor setting will be determined and applied. The BETA[2:0] bits will be automatically updated to indicate the current setting. Bit 2-0 - BETA[2:0] - These bits always reflect the current beta configuration settings. If auto-detection circuitry is enabled, these bits will be updated automatically and writing to these bits will have no effect. If the auto-detection circuitry is disabled, these bits will determine the beta configuration setting. Care should be taken when setting the BETA[2:0] bits when the auto-detection circuitry is disabled. If the Beta Compensation factor is set at a beta value that is higher than the transistor beta, the circuit SMSC EMC1412 33 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet may introduce measurement errors. When measuring a discrete thermal diode (such as 2N3904) or a CPU diode that functions like a discrete thermal diode (such as an AMD processor diode), the BETA[2:0] bits should be set to ‘111b’. Table 7.15 CPU Beta Values BETA[2:0] HEX ENABLEX 2 1 0 0h 0 0 0 0 0.11 1h 0 0 0 1 0.18 2h 0 0 1 0 0.25 3h 0 0 1 1 0.33 4h 0 1 0 0 0.43 5h 0 1 0 1 1.00 6h 0 1 1 0 2.33 7h 0 1 1 1 Disabled 8h - Fh 1 X X X Auto-detection 7.13 MINIMUM BETA External Diode Ideality Factor Register Table 7.16 Ideality Configuration Registers ADDR. 27h R/W REGISTER B7 B6 R/W External Diode Ideality Factor - - B5 B4 B3 B2 B1 IDEALITY[5:0] B0 DEFAULT 12h This register stores the ideality factors that are applied to the external diode. Table 7.17 defines each setting and the corresponding ideality factor. Beta Compensation and Resistance Error Correction automatically correct for most diode ideality errors; therefore, it is not recommended that these settings be updated without consulting SMSC. Table 7.17 Ideality Factor Look-Up Table (Diode Model) SETTING FACTOR SETTING FACTOR SETTING FACTOR 08h 0.9949 18h 1.0159 28h 1.0371 09h 0.9962 19h 1.0172 29h 1.0384 0Ah 0.9975 1Ah 1.0185 2Ah 1.0397 0Bh 0.9988 1Bh 1.0200 2Bh 1.0410 0Ch 1.0001 1Ch 1.0212 2Ch 1.0423 Revision 1.41 (02-23-12) 34 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Table 7.17 Ideality Factor Look-Up Table (Diode Model) (continued) SETTING FACTOR SETTING FACTOR SETTING FACTOR 0Dh 1.0014 1Dh 1.0226 2Dh 1.0436 0Eh 1.0027 1Eh 1.0239 2Eh 1.0449 0Fh 1.0040 1Fh 1.0253 2Fh 1.0462 10h 1.0053 20h 1.0267 30h 1.0475 11h 1.0066 21h 1.0280 31h 1.0488 12h 1.0080 22h 1.0293 32h 1.0501 13h 1.0093 23h 1.0306 33h 1.0514 14h 1.0106 24h 1.0319 34h 1.0527 15h 1.0119 25h 1.0332 35h 1.0540 16h 1.0133 26h 1.0345 36h 1.0553 17h 1.0146 27h 1.0358 37h 1.0566 For CPU substrate transistors that require the BJT transistor model, the ideality factor behaves slightly differently than for discrete diode-connected transistors. Refer to Table 7.18 when using a CPU substrate transistor. Table 7.18 Substrate Diode Ideality Factor Look-Up Table (BJT Model) SETTING FACTOR SETTING FACTOR SETTING FACTOR 08h 0.9869 18h 1.0079 28h 1.0291 09h 0.9882 19h 1.0092 29h 1.0304 0Ah 0.9895 1Ah 1.0105 2Ah 1.0317 0Bh 0.9908 1Bh 1.0120 2Bh 1.0330 0Ch 0.9921 1Ch 1.0132 2Ch 1.0343 0Dh 0.9934 1Dh 1.0146 2Dh 1.0356 0Eh 0.9947 1Eh 1.0159 2Eh 1.0369 0Fh 0.9960 1Fh 1.0173 2Fh 1.0382 10h 0.9973 20h 1.0187 30h 1.0395 11h 0.9986 21h 1.0200 31h 1.0408 12h 1.0000 22h 1.0213 32h 1.0421 13h 1.0013 23h 1.0226 33h 1.0434 14h 1.0026 24h 1.0239 34h 1.0447 15h 1.0039 25h 1.0252 35h 1.0460 16h 1.0053 26h 1.0265 36h 1.0473 17h 1.0066 27h 1.0278 37h 1.0486 SMSC EMC1412 35 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet APPLICATION NOTE: When measuring a 65nm Intel CPU, the Ideality Setting should be the default 12h. When measuring a 45nm Intel CPU, the Ideality Setting should be 15h. 7.14 Filter Control Register Table 7.19 Filter Configuration Register ADDR. R/W REGISTER B7 B6 B5 B4 B3 B2 40h R/W Filter Control - - - - - - B1 B0 DEFAULT FILTER[1:0] 00h The Filter Configuration Register controls the digital filter on the External Diode channel. Bits 1-0 - FILTER[1:0] - Control the level of digital filtering that is applied to the External Diode temperature measurement as shown in Table 7.20. See Figure 6.2 and Figure 6.3 for examples on the filter behavior. Table 7.20 FILTER Decode FILTER[1:0] 7.15 1 0 AVERAGING 0 0 Disabled (default) 0 1 Level 1 1 0 Level 1 1 1 Level 2 Product ID Register Table 7.21 Product ID Register ADDR R/W REGISTER B7 B6 B5 B4 B3 B2 B1 B0 DEFAULT FDh R Product ID 0 0 1 0 0 0 0 0 20h The Product ID Register holds a unique value that identifies the device. 7.16 SMSC ID Register Table 7.22 Manufacturer ID Register ADDR. R/W REGISTER B7 B6 B5 B4 B3 B2 B1 B0 DEFAULT FEh R SMSC ID 0 1 0 1 1 1 0 1 5Dh The Manufacturer ID register contains an 8-bit word that identifies the SMSC as the manufacturer of the EMC1412. Revision 1.41 (02-23-12) 36 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet 7.17 Revision Register Table 7.23 Revision Register ADDR. R/W REGISTER B7 B6 B5 B4 B3 B2 B1 B0 DEFAULT FFh R Revision 0 0 0 0 0 1 0 0 04h The Revision register contains an 8-bit word that identifies the die revision. SMSC EMC1412 37 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Chapter 8 Typical Operating Curves Tem perature Error vs. Am bient Tem perature (2N3904, TDIODE = 42.5°C, VDD = 3.3V) 1.0 1.0 0.8 0.8 0.6 Temperature Error (°C) Temperature Error (°C) Tem perature Error vs. Filter Capacitor (2N3904, TA = 27°C, TDIODE = 27°C, VDD = 3.3V) 0.5 0.3 0.0 -0.3 -0.5 -0.8 -1.0 0 1000 2000 3000 0.4 0.2 0.0 -0.2 -0.4 -0.6 -0.8 4000 -1.0 -40 -25 -10 Filter Capacitor (pF) 5 Temperature Error (°C) Temperature Error (°C) Revision 1.41 (02-23-12) 95 110 125 Temperature Error vs. CPU Temperature Typical 65nm CPU from major vendor (TA = 27°C, VDD = 3.3V, BETA = 011, CFILTER = 470pF) Tem perature Error vs. External Diode Tem perature (2N3904, TA = 42.5°C, VDD = 3.3V) 1.0 0.8 0.6 0.4 0.2 0.0 -0.2 -0.4 -0.6 -0.8 -1.0 -40 -25 -10 5 20 35 50 65 80 95 External Diode Tem perature (°C) 5 20 35 50 65 80 Am bient Tem perature (°C) 4 Beta Compensation Disabled 3 2 1 0 Beta Compensation Enabled -1 20 110 125 40 60 80 100 120 CPU Temperature (°C) 38 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Tem perature Error vs. Am bient Tem perature (2N3904, TDIODE = 27°C, VDD = 3.3V) 120 0.8 100 80 REC Disabled 0.6 60 0.4 40 0.2 20 REC Enabled 0.0 0 50 100 Series R (Ohm) 2.0 0 200 150 EXT2 - APD 1.5 Temperature Error (°C) 1.0 Temperature Error (°C) REC Disabled Temperature Error (°C) REC Enabled Temperature Error vs. Series Resistance EXT3 - APD 1.0 0.5 0.0 -0.5 -1.0 -1.5 -2.0 -40 -25 -10 5 20 35 50 65 80 Am bient Tem perature (°C) 95 110 125 S upply Curre nt vs. Conve rsion Ra te 1200 1100 1000 Supply Current (uA 900 800 Dy namic A v eraging Enabled 700 Dy namic A v eraging Dis abled 600 500 400 300 200 1 2 4 8 16 32 64 Conve rsion Ra te SMSC EMC1412 39 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Chapter 9 Package Information Figure 9.1 EMC1412 2mm x 3mm TDFN Package Drawing Revision 1.41 (02-23-12) 40 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Figure 9.2 EMC1412 2mm x 3mm TDFN Package Dimensions Figure 9.3 EMC1412 2mm x 3mm TDFN Package PCB Land Pattern SMSC EMC1412 41 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet REVISION HISTORY REVISION 3 D PIN 1 IDENTIFIER AREA (D/2 X E1/2) e 3 DATE RELEASED BY - - SEE SPEC FRONT PAGE FOR REVISION HISTORY 5 c E E1 2 DESCRIPTION - SEE DETAIL "A" 8X b TOP VIEW END VIEW A2 A C SEATING PLANE A1 ccc C SIDE VIEW 3-D VIEW H C NOTES: 1. ALL DIMENSIONS ARE IN MILLIMETER. 2. TOLERANCE ON THE TRUE POSITION OF THE LEADS IS ± 0.065mm MAXIMUM. 3. PACKAGE BODY DIMENSIONS "D" AND "E1" DO NOT INCLUDE MOLD PROTRUSIONS OR FLASH. MAXIMUM MOLD PROTRUSIONS OR FLASH IS 0.15 mm (0.006 INCHES) PER END AND SIDE. DIMENSIONS "D" AND "E1" ARE DETERMINED AT DATUM PLANE "H". 4. DIMENSION FOR FOOT LENGTH "L" IS MEASURED AT THE GAUGE PLANE 0.25mm ABOVE THE SEATING PLANE. 5. DETAILS OF PIN 1 IDENTIFIER ARE OPTIONAL, BUT MUST BE LOCATED WITHIN THE ZONE INDICATED. GAUGE PLANE 0.25 SEATING PLANE 0° - 8° 4 L UNLESS OTHERWISE SPECIFIED DIMENSIONS ARE IN MILLIMETERS AND TOLERANCES ARE: L1 DECIMAL ±0.1 X.X X.XX ±0.05 X.XXX ±0.025 THIRD ANGLE PROJECTION 80 ARKAY DRIVE HAUPPAUGE, NY 11788 USA ANGULAR ±1° TITLE DETAIL "A" NAME DIM AND TOL PER ASME Y14.5M - 1994 MATERIAL - SCALE: 3/1 FINISH - DATE S.K.ILIEV 7/05/04 CHECKED S.K.ILIEV S.K.ILIEV REV DWG NUMBER MO-8-TSSOP-3x3 7/05/04 APPROVED PRINT WITH "SCALE TO FIT" DO NOT SCALE DRAWING PACKAGE OUTLINE 8 PIN TSSOP, 3x3 MM BODY, 0.65 MM PITCH DRAWN D SHEET STD COMPLIANCE SCALE 7/07/04 1:1 JEDEC: MO-187 / D 1 OF 1 Figure 9.4 8-Pin MSOP / TSSOP Package Revision 1.41 (02-23-12) 42 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet 9.1 Package Markings The devices will be marked as shown in Figure 9.5, Figure 9.6 and Figure 9.7. TOP 2x 0.6 LINE 1: Preface, First digit of Device Code E 1 LINE 2: Second digit of Device Code, Revision 5 R PIN 1 LINES 1 & 2: CENTER HORIZONTAL ALIGNMENT LINE 3: AS SHOWN BOTTOM BOTTOM MARKING IS NOT ALLOWED Figure 9.5 EMC1412-1 8-Pin TDFN Package Markings SMSC EMC1412 43 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet TOP 2x 0.6 LINE 1: Preface, First digit of Device Code E 3 LINE 2: Second digit of Device Code, Revision 4 R PIN 1 LINES 1 & 2: CENTER HORIZONTAL ALIGNMENT LINE 3: AS SHOWN BOTTOM BOTTOM MARKING IS NOT ALLOWED Figure 9.6 EMC1412-A 8-Pin TDFN Package Markings Revision 1.41 (02-23-12) 44 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet TOP LINE: 1-T – Device Number 1 4 1 2 LINE: 2-T Version, Revision, Country Code (VRCC) V R C C 2x 1.5pt e3 PB-FREE/GREEN SYMBOL (Matte Sn) ALL TOP LINES CENTER HORIZONTAL ALIGNMENT PIN 1 BOTTOM PIN 1 LINE: 1-B – Date Code (YYWW) Y Y W W LINE: 2-B – First 3 Digits of Lot Number 1 2 3 LINE: 3-B – Last 4 Digits of Lot Number 4 5 6 a 3x 1.5pt Figure 9.7 EMC1412 8-Pin MSOP Package Markings SMSC EMC1412 45 DATASHEET Revision 1.41 (02-23-12) Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Chapter 10 Document Revision History Table 10.1 Customer Revision History REVISION LEVEL & DATE SECTION/FIGURE/ENTRY CORRECTION Rev. 1.41 (02-23-12) Chapter 3, Pin Description Labeled exposed pad in pinout figure and added row in pin description table. Recommendation is to ground the exposed pad. Rev. 1.40 (01-05-12) Table 4.3, "SMBus Electrical Specifications" Added conditions for tHD:DAT. Data hold time minimum of 0.3µs is required when receiving from the master. Section 5.1.8, "SMBus and I2C Compatibility" Renamed from “SMBus and I2C Compliance.” First paragraph, added first sentence: “The EMC1412 is compatible with SMBus and I2C.” And added last sentence: “For information on using the EMC1412 in an I2C system, refer to SMSC AN 14.0 SMSC Dedicated Slave Devices in I2C Systems.” Table 4.2, "Electrical Specifications" Filter MAX changed from “2.5nF” to “2.7nF”. Section 7.17, "Revision Register" Set revision ID to 04h. Chapter 5, System Management Bus Interface Protocol Updated error on ACK bit settings and reorganized chapter information and moved ALERT pin considerations. Chapter 6, Product Description Reorganized information for temperature monitoring and ALERT pin considerations. Rev. 1.37 (12-23-09) Section 7.17, "Revision Register" Changed default from 01h to 03h to match the actual value. Rev. 1.36 (09-19-09) Ordering Information Added EMC1412-1-AC3-TR in an 8-pin TDFN package. Section 4.1, "Absolute Maximum Ratings" Updated voltage on 5V tolerant pins with pull up from -0.3 to 3.6 to 0 to 3.6. Added thermal characteristics for TDFN package. Chapter 9, Package Information Added package information for the TDFN. Section 9.1, "Package Markings" Added package marking information for the TDFN. Pin Table Identified 5V tolerant pins. Added the following application note below table: “For the 5V tolerant pins that have a pull-up resistor (SMCLK, SMDATA, THERM, ALERT), the voltage difference between VDD and the pull-up voltage must never exceed 3.6V.” Rev. 1.38 (09-30-10) Rev. 1.35 (05-06-09) Revision 1.41 (02-23-12) 46 DATASHEET SMSC EMC1412 Multiple Channel 1°C Temperature Sensor with Beta Compensation Datasheet Table 10.1 Customer Revision History (continued) REVISION LEVEL & DATE SECTION/FIGURE/ENTRY Table 4.1, "Absolute Maximum Ratings" CORRECTION Updated voltage limits for 5V tolerant pins with pull-up resistors. Added the following note below table: “For the 5V tolerant pins that have a pull-up resistor (SMCLK, SMDATA, THERM, ALERT), the pull-up voltage must not exceed 3.6V when the device is unpowered.” Table 4.2, "Electrical Specifications" Rev. 1.34 (12-02-08) SMSC EMC1412 Added leakage current Initial document creation 47 DATASHEET Revision 1.41 (02-23-12)