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 features
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
Support for diodes requiring the BJT/transistor model
— Supports 65nm and lower geometry CPU thermal
diodes
Features
Pin and register compatible with EMC1412
Automatically determines external diode type and
optimal settings
Resistance 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
DIODE
< 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
1.8V SMBus operation
Programmable temperature limits for ALERT/THERM2
(85°C default high limit and 0°C default low limit) and
THERM (85°C default)
Available in small 8-pin 2mm x 3mm TDFN RoHS
compliant package
Available in small 8-pin 3mm x 3mm DFN RoHS
compliant package
VDD = 3.3V
V
DD
EMC1182
Switching
Current
Limit Comparator
Digital Mux
External
Temperature
Register(s)
Internal
Temperature
Register
Digital Mux
DP
1
D
N1
Analog
Mux
ΔΣADC
Conversion Rate Register
Low Limit Registers
SMBus Interface
SMCLK
SMDATA
EMC1182
SMDATA
High Limit Registers
THERM Limit Register
THERM Hysteresis
Register
Configuration Register
THERM / ADDR
THERM / ADDR
SMBus Address Decode
Status Registers
1.8V
1.8V – 3.3V
VDD
CPU / GPU
DP
Thermal
Junction
DN
SMCLK
SMBus
Interface
ALERT / THERM2
Host
Internal
Temp Diode
ALERT / THERM2
Interupt Masking
GND
Power Control
GND
* Technology covered under the US patent 7,193,543.
SMSC EMC1182
Revision 1.0 (07-11-13)
DATASHEET
SMSC [ SMSC CORPORATION ]
