EMC2101
SMBus Fan Control
with 1°C Accurate
Temperature Monitoring
PRODUCT FEATURES
GENERAL DESCRIPTION
The EMC2101 is an SMBus 2.0 compliant, integrated
fan control solution complete with two temperature
monitors, one external and one internal. Each
temperature channel has programmable high limits that
can assert an interrupt.
The fan drive is selectable as a Pulse Width Modulator
(PWM) or Linear (DAC) output. The fan control output,
whether the PWM or DAC drive circuit, uses an eight
position look-up table to allow the user to program the
fan speed profile based on temperature. The DAC out-
put ranges from 0V to V
DD
with up to 6 bit resolution
while the PWM output has a range of 0% to 100% with
up to 64 steps.
The EMC2101 has an option to automatically upload the
contents of an attached SMBus compatible EEPROM for
auto-programming upon power up.
Advanced thermal sensing enables reduced validation
and characterization time as well as accurately operat-
ing with smaller-geometry processors. Resistance Error
Correction (REC) automatically corrects the offset errors
of board trace and device resistance, up to 100Ω. Auto-
matic Beta Compensation allows the user the flexibility
to design applications that include processor substrate
transistors.
Datasheet
FEATURES
Automatic Beta Compensation
Resistance Error Correction
Self-programming with available SMBus compatible
EEPROM
Selectable PWM or DAC fan driver output
Temperature Monitors
— External channel ±1°C accuracy
— Internal channel ±2°C accuracy
3.3 Volt Operation (5 Volt Tolerant Input Buffers)
SMBus 2.0 Compliant Interface, supports TIMEOUT
8-Pin MSOP Lead-free RoHS Compliant Packages
8-Pin SOIC Lead-free RoHS Compliant Package
APPLICATIONS
Graphics Processors
Embedded Application Fan Drive
PWM Controller + Temp Sensor
BLOCK DIAGRAM
V
DD
EMC2101
Address Pointer Register
Switching
Current
Conversion Rate Register
Limit Comparator
Internal High Limit Register
External High Limit Register
External TCRIT Limit Register
DP
Analog
Mux
DN
Internal
Temp Diode
ΔΣ
ADC
External
Temperature
Register
Internal
Temperature
Register
Fan Control
Look-Up Table
Configuration Register
SMBus Interface
SMCLK
SMDATA
ALERT / TACH
PWM Driver
FAN
DAC Driver
Fan Control
Logic
GND
Status Registers
Interupt Masking
SMSC EMC2101
Revision 2.53 (03-13-07)
DATASHEET
SMSC [ SMSC CORPORATION ]
