EMC2101 Datasheet, PDF (1/55 Pages) SMSC Corporation – SMBus Fan Control with 1°C Accurate Temperature Monitoring

EMC2101
SMBus Fan Control
with 1°C Accurate
Temperature Monitoring
PRODUCT FEATURES
Datasheet
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.
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
VDD
EMC2101
Switching
Current
DP
Analog
Mux
ΔΣ ADC
DN
Internal
Temp Diode
External
Temperature
Register
Internal
Temperature
Register
PWM Driver
FAN
DAC Driver
Fan Control
Logic
SMSC EMC2101
GND
Status Registers
DATASHEET
Address Pointer Register
Conversion Rate Register
Internal High Limit Register
External High Limit Register
External TCRIT Limit Register
Fan Control
Look-Up Table
Configuration Register
Interupt Masking
SMCLK
SMDATA
ALERT / TACH
Revision 2.53 (03-13-07)