Datasheet EMC1182 Datasheet

EMC1182

CPU / GPU

EMC1182

Host

DP

DN

SMDATA

Thermal
Junction

SMCLK

SMBus

Interface

THERM / ADDR

ALERT / THERM2

Power Control

VDD

GND

VDD = 3.3V

1.8V – 3.3V

1.8V

THERM / ADDR

ALERT / THERM2

Internal

Temp Diode

Switching

Current

Analog

Mux

Internal

Temperature

Register

Digital Mux

Digital Mux

Limit Comparator

Low Limit Registers
High Limit Registers

Conversion Rate Register

Interupt Masking

Status Registers

Configuration Register

SMBus Interface

SMCLK
SMDATA

DP

1

D

N1

V

DD

GND

External

Temperature

Register(s)

ΔΣADC

THERM Limit Register

THERM Hysteresis

Register

SMBus Address Decode

EMC1182

Dual Channel 1°C Temperature Sensor with Beta
Compensation and 1.8V SMBus Communications

PRODUCT FEATURES

General Description

The EMC1182 is a high accuracy, low cost, 1.8V System
Management Bus (SMBus) compatible temperature sensor.
Advanced features such as Resistance Error Correction (REC),
Beta Compensation (to support CPU diodes requiring the
BJT/transistor model including 65nm and lower geometry
processors) and automatic diode type detection combine to
provide a robust solution for complex environmental monitoring
applications. The ability to communicate at 1.8V SMBus levels
provides compatible I/O for the advanced processors found in
today’s tablet and smartphone applications.

The EMC1182 monitors two temperature channels (one
external and one internal), providing ±1°C accuracy for both
external and internal diode temperatures.

REC automatically eliminates the temperature error caused by
series resistance allowing greater flexibility in routing thermal
diodes. Frequency hopping* and analog filters ensure remote
diode traces can be as far as eight (8) inches without degrading
the signal. 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 featu res
plus ±1°C measurement accuracy provide a low-cost, highly
flexible and accurate solution for critical temperature monitoring
applications.

Datasheet

Applications

 Notebook Computers
 Desktop Computers
 Industrial
 Embedded applications

Features

 Support for diodes requiring the BJT/transistor model

— Supports 65nm and lower geometry CPU thermal

diodes

 Pin and register compatible with EMC1412
 Automatically determines external diode type and

optimal settings

 R esistance Error Correction
 Frequency hops the remote sample frequency to reject

DC converter and other coherent noise sources*

 Consecutive Alert queue to further reduce false Alerts
 Up to 1 External Temperature Monitor

— 25°C typ, ±1°C max accuracy (20°C < T
— 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
 1.8V SMBus operation
 Programmable temperature limits for ALERT/THERM2

(85°C default high limit and 0°C default low limit) and
THERM

 Available in small 8-pin 2mm x 3mm TDFN RoHS

(85°C default)

compliant package

 Available in small 8-pin 3mm x 3mm DFN RoHS

compliant package

DIODE

< 110°C)

DATASHEET

* Technology covered under the US patent 7,193,543.

SMSC EMC1182 Revision 1.0 (07-11-13)

Dual Channel 1°C Temperature Sensor with Beta Compensation and 1.8V SMBus Communications

Datasheet

Ordering Information:

ORDERING NUMBER PACKAGE FEATURES

SMBUS

ADDRESS

EMC1182-A-AC3-TR 8-pin TDFN 2mm x 3mm

(RoHS compliant)

EMC1182-1-AIA-TR 8-pin DFN 3mm x 3mm

(RoHS compliant)

EMC1182-1-AC3-TR 8-pin TDFN 2mm x 3mm

(RoHS compliant)

EMC1182-2-AIA-TR 8-pin DFN 3mm x 3mm

(RoHS compliant)

EMC1182-2-AC3-TR 8-pin TDFN 2mm x 3mm

(RoHS compliant)

This product meets the halogen maximum concentration values per IEC 61249-2-21

For RoHS compliance and environmental information, please visit www.smsc.com/rohs

Please contact your SMSC sales representative for additional documentation related to this product
such as application notes, anomaly sheets, and design guidelines.

Two temperature sensors, ALERT/THERM2

and THERM

Two temperature sensors, ALERT

pins, fixed SMBus address

/THERM2

and THERM pins, fixed SMBus address

Two temperature sensors, ALERT

/THERM2

and THERM pins, fixed SMBus address

Two temperature sensors, ALERT

/THERM2

and THERM pins, fixed SMBus address

Two temperature sensors, ALERT

/THERM2

and THERM pins, fixed SMBus address

Selectable via

THERM pull-up

1001_100(r/w

1001_100(r/w

1001_101(r/w

1001_101(r/w

)

)

)

)

Copyright © 2013 SMSC or its subsidiaries. All rights reserved.
Circuit diagrams and other information relating to SMSC products are included as a means of illustr ating typical applications. Conse quently, 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. SMS C
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.

The Microchip name and logo, and the Microchip logo are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries.

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; REGAR DLESS OF THE FORM OF ACTION, WHETHER BASED ON CONTRAC T;
TORT; NEGLIGENCE OF SMSC OR OTHERS; ST RICT LIABILITY; BREACH OF WARRANTY; OR OTHERWISE; WHETHER OR NOT ANY REMEDY OF BUYER IS HELD
TO HAVE FAILED OF ITS ES SENTIAL PURPOSE, AND WHETHER OR NOT SMSC HAS BEEN ADVISED OF THE P OSSIBILITY OF SUCH DAMAGES.

Revision 1.0 (07-11-13) 2 SMSC EMC1182

DATASHEET

Dual Channel 1°C Temperature Sensor with Beta Compensation and 1.8V SMBus Communications

Datasheet

Table of Contents

Chapter 1 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Chapter 2 Pin Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Chapter 3 Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

3.1 Absolute Maximum Ratings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

3.2 Electrical Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

3.3 SMBus Electrical Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Chapter 4 System Management Bus Interface Protocol. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

4.1 Communications Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

4.1.1 SMBus Start Bit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

4.1.2 SMBus Address and RD / WR

4.1.3 THERM

4.1.5 SMBus Data Bytes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

4.1.6 SMBus ACK and NACK Bits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

4.1.7 SMBus Stop Bit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

4.1.8 SMBus Timeout. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

4.1.9 SMBus and I

4.2 SMBus Protocols. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

4.2.1 Write Byte . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

4.2.2 Read Byte . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

4.2.3 Send Byte . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

4.2.4 Receive Byte . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

4.3 Alert Response Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Pin Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

2

C Compatibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Bit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Chapter 5 Product Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

5.1 Modes of Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

5.2 Conversion Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

5.3 Dynamic Averaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

5.4 THERM

5.5 ALERT / THERM2 Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

5.6 Temperature Measurement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

5.7 Diode Faults . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

5.8 Consecutive Alerts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

5.9 Digital Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

5.10 Temperature Measurement Results and Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

5.4.1 THERM

5.5.1 ALERT

5.5.2 ALERT

5.6.1 Beta Compensation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

5.6.2 Resistance Error Correction (REC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

5.6.3 Programmable External Diode Ideality Factor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Pin Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

/ THERM2 Pin InterruptALERT Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

/ THERM2 Pin ComparatorTHERM Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Chapter 6 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

6.1 Data Read Interlock. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

6.2 Temperature Data Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

6.3 Status Register 02h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

SMSC EMC1182 3 Revision 1.0 (07-11-13)

DATASHEET

Dual Channel 1°C Temperature Sensor with Beta Compensation and 1.8V SMBus Communications

Datasheet

6.4 Configuration Register 03h / 09h. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

6.5 Conversion Rate Register 04h / 0Ah. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

6.6 Limit Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

6.7 Scratchpad Registers 11h and 12h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

6.8 One Shot Register 0Fh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

6.9 Therm Limit Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

6.10 Channel Mask Register 1Fh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

6.11 Consecutive ALERT Register 22h. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

6.12 Beta Configuration Register 25h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

6.13 External Diode Ideality Factor Register 27h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

6.14 Filter Control Register 40h. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

6.15 Product ID Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

6.16 SMSC ID Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

6.17 Revision Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Chapter 7 Typical Operating Curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Chapter 8 Package Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

8.1 Package Markings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Chapter 9 Datasheet Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Revision 1.0 (07-11-13) 4 SMSC EMC1182

DATASHEET

Dual Channel 1°C Temperature Sensor with Beta Compensation and 1.8V SMBus Communications

Datasheet

List of Figures

Figure 1.1 EMC1182 Block Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Figure 2.1 EMC1182 Pin Diagram, TDFN-8 2mm x 3mm / DFN-8 3mm x 3mm . . . . . . . . . . . . . . . . . . . 8

Figure 4.1 SMBus Timing Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Figure 4.4 Isolating the THERM pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Figure 5.1 System Diagram for EMC1182 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Figure 5.2 Isolating THERM
Figure 5.3 Isolating ALERT

Figure 5.4 Temperature Filter Step Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Figure 5.5 Temperature Filter Impulse Response. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Figure 8.1 2mm x 3mm TDFN Package Drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Figure 8.3 2mm x 3mm TDFN Package PCB Land Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Figure 8.2 2mm x 3mm TDFN Package Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Figure 8.4 3mm x 3mm DFN Package Drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Figure 8.5 3mm x 3mm DFN Package Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Figure 8.6 8 Pin DFN PCB Footprint. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Figure 8.7 EMC1182-1 8-Pin TDFN Package Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Figure 8.8 EMC1182-2 8-Pin TDFN Package Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Figure 8.9 EMC1182-A 8-Pin TDFN Package Markings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Figure 8.10 EMC1182-1 8-Pin DFN Package Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Figure 8.11 EMC1182-2 8-Pin DFN Package Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

and SYS_SHDN Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

SMSC EMC1182 5 Revision 1.0 (07-11-13)

DATASHEET

Dual Channel 1°C Temperature Sensor with Beta Compensation and 1.8V SMBus Communications

Datasheet

List of Tables

Table 2.1 EMC1182 Pin Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Table 2.2 Pin Types. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Table 3.1 Absolute Maximum Ratings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Table 3.2 Electrical Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Table 3.3 SMBus Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Table 4.1 SMBus Address Decode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Table 4.1 Protocol Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Table 4.2 Write Byte Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Table 4.3 Read Byte Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Table 4.4 Send Byte Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Table 4.5 Receive Byte Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Table 4.6 Alert Response Address Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Table 5.1 Supply Curr en t vs. Co nve r sion Rat e for EMC11 82 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Table 5.2 Temperature Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Table 6.1 Register Set in Hexadecimal Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Table 6.2 Temperature Data Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Table 6.3 Status Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Table 6.4 Configuration Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Table 6.5 Conversion Rate Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Table 6.6 Conversion Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Table 6.7 Temperature Limit Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Table 6.8 Scratchpad Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Table 6.9 Therm Limit Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Table 6.10 Channel Mask Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Table 6.11 Consecutive ALERT Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Table 6.12 Consecutive Alert / Therm Settings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Table 6.13 Beta Configuration Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Table 6.14 Ideality Configuration Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Table 6.15 Ideality Factor Look-Up Table (Diode Model) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Table 6.16 Substrate Diode Ideality Factor Look- Up Table (BJT Model) . . . . . . . . . . . . . . . . . . . . . . . . . 36

Table 6.17 Filter Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Table 6.18 FILTER Decode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Table 6.19 Product ID Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Table 6.20 Manufacturer ID Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Table 6.21 Revision Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Table 9.1 Customer Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Revision 1.0 (07-11-13) 6 SMSC EMC1182

DATASHEET

Internal Temp

Diode

Switching

Current

Analog

Mux

Internal

Temperature Register

Digital Mux

Digital Mux

Limit Comparator

Low Limit Registers

High Limit Registers

Conversion Rate Register

Interupt Masking

Status Registers

Configuration Register

SMBus Interface

SMCLK

SMDATA

DP

DN

V

DD

GND

External Temperature

Register(s)

ΔΣ ADC

THERM Limit Register

THERM Hysteresis Register

SMBus Address Decode

ALERT

EMC1182

THERM / ADDR

Dual Channel 1°C Temperature Sensor with Beta Compensation and 1.8V SMBus Communications

Chapter 1 Block Diagram

Datasheet

Figure 1.1 EMC1182 Block Diagram

SMSC EMC1182 7 Revision 1.0 (07-11-13)

DATASHEET

SMDATA

SMCLK

1
2
3
4

ALERT / THERM2

DN

THERM / ADDR

GND

Exposed pad

DP

VDD

8
7
6
5

EMC1182

Dual Channel 1°C Temperature Sensor with Beta Compensation and 1.8V SMBus Communications

Datasheet

Chapter 2 Pin Description

Figure 2.1 EMC1182 Pin Diagram, TDFN-8 2mm x 3mm / DFN-8 3mm x 3mm

Table 2.1 EMC1182 Pin Description

PIN NUMBER NAME FUNCTION TYPE

1 VDD Power supply Power
2 DP External diode positive (anode) connection AIO
3 DN External diode negative (cathode) connection AIO

THERM

4 THERM

5 GND Ground Power

6ALERT

7SMDATA

8 SMCLK SMBus Clock input - requires pull-up resistor DI (5V)

/ ADDR

/ THERM2

signal - requires pull-up resistor
ADDR - Selects SMBus address based on pull-

up resistor

Active low digital ALERT / THERM2 output
signal - requires pull-up resistor

SMBus Data input/output - requires pull-up
resistor

- Active low Critical THERM output

OD (5V)

OD (5V)

OD (5V)

DIOD (5V)

Bottom Pad Exposed Pad

Revision 1.0 (07-11-13) 8 SMSC EMC1182

Not internally connected, but recommend
grounding.

-

DATASHEET

Dual Channel 1°C Temperature Sensor with Beta Compensation and 1.8V SMBus Communications

The pin types are described Table 2.2.

Ta ble 2.2 Pin Typ es

PIN TYPE DESCRIPTION

Power This pin is used to supply power or ground to the device.

AIO Analog Input / Output -This pin is used as an I/O for analog signals.

DI Digital Input - This pin is used as a digital input. This pin is 5V tolerant.

Datasheet

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 resi stor. 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 EMC1182 9 Revision 1.0 (07-11-13)

DATASHEET

Dual Channel 1°C Temperature Sensor with Beta Compensation and 1.8V SMBus Communications

Datasheet

Chapter 3 Electrical Specifications

3.1 Absolute Maximum Ratings

Table 3.1 Abso lute Maximum Ratings

DESCRIPTION RATING UNIT

Supply Voltage (V
Voltage on 5V tolerant pins (V
Voltage on 5V tolerant pins (|V
Voltage on any other pin to Ground -0.3 to V

) -0.3 to 4.0 V

DD

) -0.3 to 5.5 V

5VT_pin

- VDD|) (see Note 3.1)0 to 3.6 V

5VT_pin

+0.3 V

DD

Operating Temperature Range -40 to +125 °C
Storage Temperature Range -55 to +150 °C
Lead Temperature Range Refer to JEDEC Spec. J-STD-020
Package Thermal Characteristics for TDFN-8

Thermal Resistance (θ

)89°C/W

j-a

ESD Rating, All pins HBM 2000 V

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 conditio n above those indicated
in the operation sections of this specification is not implied.

Note 3.1 For the 5V tolerant pins that have a pull-up resistor (SMCLK, SMDATA, THERM

ALERT

/ THERM2), the pull-up voltage must not exceed 3.6V when the device is

unpowered.

, and

3.2 Electrical Specifications

Table 3.2 Electrical Specifications

V

= 3.0V to 3.6V, TA = -40°C to 125°C, all typical values at TA = 27°C unless otherwise noted.

DD

CHARACTERISTIC SYMBOL MIN T YP MAX UNITS CONDITIONS

DC Power
Supply Voltage V
Supply Current I

Revision 1.0 (07-11-13) 10 SMSC EMC1182

DD

DD

3.0 3.3 3.6 V
200 410 µA 0.0625 conversion / sec, dynamic

averaging disabled

215 425 µA 1 conversion / sec, dynamic

averaging disabled

DATASHEET

Dual Channel 1°C Temperature Sensor with Beta Compensation and 1.8V SMBus Communications

Table 3.2 Electrical Specifications (co ntinu ed)

V

= 3.0V to 3.6V, TA = -40°C to 125°C, all typical values at TA = 27°C unless otherwise noted.

DD

CHARACTERISTIC SYMBOL MIN TYP MAX UNITS CONDITIONS

Datasheet

325 465 µA 4 conversions / sec, dynamic

averaging disabled

890 1050 µA 4 conversions / sec, dynamic

averaging enabled

1120 µA > 16 conversions / sec, dynamic

averaging enabled

Standby Supply Current I

DD

170 230 µA Device in Standby mode, no SMBus

communications, ALERT and
THERM pins not asserted.

Internal Temperature Monitor

Temperature Accuracy ±0.25 ±1 °C -5°C < TA < 100°C

±2 °C -40°C < T

< 125°C

A

Temperature Resolution 0.125 °C

External Temperature Monitor

Temperature Accuracy ±0.25 ±1 °C +20°C < T

0°C < TA < 100°C

±0.5 ±2 °C -40°C < T

DIODE

DIODE

< +110°C

< 127°C
Temperature Resolution 0.125 °C
Conversion Time all

Channels

t

CONV

190 ms default settings

Capacitive Filter C

Output Low Voltage V
Leakage Current I

FILTER

OL

LEAK

ALERT

0.4 V I

2.2 2.7 nF Connected across external diode

/ THERM2 and THERM pins

= 8mA

SINK

±5 µA ALERT / THERM2 and SYS_SHDN

pins
Device powered or unpowered
TA < 85°C
pull-up voltage < 3.6V

SMSC EMC1182 11 Revision 1.0 (07-11-13)

DATASHEET

Dual Channel 1°C Temperature Sensor with Beta Compensation and 1.8V SMBus Communications

Datasheet

3.3 SMBus Electrical Characteristics

Table 3.3 SMBus Electrical Specifications

V

= 3.0 to 3.6V, TA = -40°C to 125°C, all typical values are at TA = 27°C unless otherwise noted.

DD

CHARACTERISTIC SYMBOL MIN TYP MAX UNITS CONDITIONS

SMBus Interface

Input High Voltage V

Input Low Voltage V

Leakage Current I

IH

IL

LEAK

1.4 V

V 5V Tolerant. Voltage threshold

DD

-0.3 0.8 V 5V Tolerant. Voltage threshold

±5 µA Powered or unpowered

Hysteresis 50 mV
Input Capacitance C
Output Low Sink Current I

OL

IN

8.2 15 mA SMDATA = 0.4V

5pF

SMBus Timing
Clock Frequency f
Spike Suppression t
Bus Free Time Stop to

Start
Hold Time: Start t
Setup Time: Start t
Setup Time: Stop t
Data Hold Time t
Data Hold Time t
Data Setup Time t
Clock Low Period t
Clock High Period t
Clock/Data Fall time t
Clock/Data Rise time t
Capacitive Load C
Timeout t

SMB

SP

t

BUF

HD:STA

SU:STA

SU:STO

HD:DAT

HD:DAT

SU:DAT

LOW

HIGH

FALL

RISE

LOAD

TIMEOUT

10 400 kHz

50 ns

1.3 µs

0.6 µs

0.6 µs

0.6 µs
0 µs When transmitting to the master

0.3 µs When receiving from the master
100 ns

1.3 µs

0.6 µs
300 ns Min = 20+0.1C
300 ns Min = 20+0.1C
400 pF per bus line

25 35 ms Disabled by default

based on 1.8V operation

based on 1.8V operation

TA < 85°C

ns

LOAD

ns

LOAD

Revision 1.0 (07-11-13) 12 SMSC EMC1182

DATASHEET

Dual Channel 1°C Temperature Sensor with Beta Compensation and 1.8V SMBus Communications

SMDATA

SMCLK

T

BUF

P

S

S - Start Condition

P - Stop Condition

PS

T

HIGH

T

LOW

T

HD:STA

T

SU:STO

T

HD:STA

T

HD:DAT

T

SU:DAT

T

SU:STA

T

FALL

T

RISE

Datasheet

Chapter 4 System Management Bus Interface Protocol

4.1 Communications Protocol

The EMC1182 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

For the first 15ms after power-up the device may not respond to SMBus communications.

.

Figure 4.1.

Figure 4.1 SMBus Timing Diagram

4.1.1 SMBu s 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.

4.1.2 SMBus Add ress 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 da ta to the client device. If this RD / WR bit
is a logic ‘1’, the SMBus Host is reading data from the client device.

The EMC1182-A SMBus slave address is determined by the pull-up resistor on the THERM pin as
shown in

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 curre nt / resistor relationship. This pin voltage
is compared against a threshold that determines the value of the pull-up resisto r.

SMSC EMC1182 13 Revision 1.0 (07-11-13)

Table 4.1, "SMBus Address Decode".

T able 4.1 SMBus Address Decode

PULL UP RESISTOR ON

THERM

PIN (±5%) SMBUS ADDRESS

4.7k 1 111_100(r/w

6.8k 1011_100(r/w

DATASHEET

)b
)b

Dual Channel 1°C Temperature Sensor with Beta Compensation and 1.8V SMBus Communications

+3.3V

Shared THERM

22K

4.7K ­33K

+2.5 - 5V

EMC1182

8

7

6

5

SMDATA

SMCLK

1

2

3

4

ALERT / ADDR

VDD

DP

DN

THERM

GND

Datasheet

Ta ble 4.1 SMBus Add ress Decode (continued)

PULL UP RESISTOR ON

THERM

PIN (±5%) SMBUS ADDRESS

10k 1001_100(r/w)b
15k 1101_100(r/w
22k 0011_100(r/w
33k 01 11_100(r/w

The EMC1182-1 SMBus address is hard coded to 1001_100(r/w).
The EMC1182-2 SMBus address is hard coded to 1001_101(r/w).

4.1.3 THERM Pin Considerations

Because of the decode method used to determine the SMBus Address, it is important that the pull-up
resistance on the
resistor on the THERM pin must be connected to the same 3.3V suppl y 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 4.4, "Isolating the THERM pi n".

THERM pin be within the tolerances shown in Table 4.1. Additionally, the pull-up

)b
)b
)b

Figure 4.4 Isolating the THERM

pin

4.1.5 SMBus Data Bytes

All SMBus Data bytes are sent most significant bit first and composed of 8-bits of information.

4.1.6 SMBus ACK and NACK Bits

The SMBus client will acknowledge all data bytes that it receives. This is done by the cl ient device
pulling the SMBus data line low after the 8th bit of each byte that is transmitted. This applies to the
Write Byte protocol.

Revision 1.0 (07-11-13) 14 SMSC EMC1182

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.

DATASHEET

Dual Channel 1°C Temperature Sensor with Beta Compensation and 1.8V SMBus Communications

4.1.7 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 rese t its client interface and prepare
to receive further communications.

4.1.8 SMBus Timeout

Datasheet

The EMC1182 supports SMBus Timeout. If the clock line is held low for longer than t
device will reset its SMBus protocol. This function can be enabled by setting the TIMEOUT bit (see

Section 6.11, "Consecutive ALERT Register 22h").

4.1.9 SMBus and I2C Compatibility

The EMC1182 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 EMC1182 in an I2C system, refer to SMSC AN 14.0 SMSC Dedicated Slave
Devices in I

1. EMC1182 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 EMC1182 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 op tiona l for SMBus).

Attempting to communicate with the EMC1182 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.

2

C Systems.

4.2 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 4.1.

TIMEOUT

, the

Ta ble 4.1 Protocol Format

DATA SENT
TO DEVICE

# of bits sent # of bits sent

SMSC EMC1182 15 Revision 1.0 (07-11-13)

DATASHEET

DATA SENT TO

THE HOST