EMC1184 Datasheet, PDF (1/48 Pages) SMSC Corporation – Quad Channel 1°C Temperature Sensor with Beta

EMC1184
Quad Channel 1°C Temperature Sensor with Beta
Compensation and 1.8V SMBus Communications
PRODUCT FEATURES
General Description
The EMC1184 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 EMC1184 monitors four temperature (three external and
one internal) channels, 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
Features
 Programmable SMBus address
 Support for diodes requiring the BJT/transistor model
— Supports 65nm and lower geometry CPU thermal
diodes
 Pin and register compatible with EMC1414
 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 3 External Temperature Monitors
— 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
 Anti-parallel diodes for extra diode support 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 10-pin 3mm x 3mm DFN RoHS
compliant package
DP1
DN1
DP2 / DN3
DN2 / DP3
ALERT / THERM2
THERM / ADDR
EMC1184
Switching
Current
Analog
Mux
ΔΣ ADC
Internal Temp
Diode
Interupt Masking
SMBus Address Decode
VDD
External
Temperature
Register(s)
Internal
Temperature
Register
GND
Status Registers
Conversion Rate Register
Low Limit Registers
High Limit Registers
THERM Limit Register
THERM Hysteresis Register
Configuration Register
* Technology covered under the US patent 7,193,543.
SMCLK
SMDATA
CPU /
GPU
Thermal
Junction
Anti-Parallel
Diode
DP1 _VDD
DN1
EMC1184
DP2 / DN3
DN2 / DP3
GND
VDD =
3.3V
1.8V 1.8V-3.3V
Host
SMCLK
SMDATA
ALERT / THERM2
SMBus
Interface
THERM / ADDR
Power
Control
SMSC EMC1184
DATASHEET
Revision 1.0 (07-11-13)