ADT7473_11 Datasheet, PDF (1/74 Pages) ON Semiconductor – dbCOOL Remote Thermal Monitor and Fan Control

ADT7473
dbCOOLt Remote Thermal
Monitor and Fan Control
The ADT7473/ADT7473−1 dbCOOL controller is a thermal
monitor and multiple PWM fan controller for noise sensitive or power
sensitive applications requiring active system cooling. The
ADT7473/ADT7473−1 can drive a fan using either a low or high
frequency drive signal, monitor the temperature of up to two remote
sensor diodes plus its own internal temperature, and measure and
control the speed of up to four fans so they operate at the lowest
possible speed for minimum acoustic noise.
The automatic fan speed control loop optimizes fan speed for a
given temperature. A unique dynamic T_MIN control mode enables the
system thermals/acoustics to be intelligently managed. The
effectiveness of the system’s thermal solution can be monitored using
the THERM input. The ADT7473/ADT7473−1 also provide critical
thermal protection to the system using the bidirectional THERM pin
as an output to prevent system or component overheating.
FEATURES
• Controls and Monitors Up to 4 Fans
• High and Low Frequency Fan Drive Signal
• 1 On−Chip and 2 Remote Temperature Sensors
• Series Resistance Cancellation on the Remote Channel
• Extended Temperature Measurement Range, Up to 191°C
• Dynamic T_MIN Control Mode Intelligently Optimizes System
Acoustics
• Automatic Fan Speed Control Mode Controls System Cooling Based
on Measured Temperature
• Enhanced Acoustic Mode Dramatically Reduces User Perception of
Changing Fan Speeds
• Thermal Protection Feature via THERM Output
• Monitors Performance Impact of Intel Pentium^R 4 Processor
• Thermal Control Circuit via THERM Input
• 3−Wire and 4−Wire Fan Speed Measurement
• Limit Comparison of All Monitored Values
• Meets SMBus 2.0 Electrical Specifications
(Fully SMBus 1.1 Compliant)
• These Devices are Pb−Free, Halogen Free/BFR Free and are RoHS
Compliant
http://onsemi.com
QSOP−16
CASE 492
MARKING DIAGRAMS
ADT747
3ARQZ
#YYWW
xxxx
ADT
7473−1
ARQZ
xxxx
ADT7473
ADT7473−1
#
= Pb−Free Package
YYWW = Date Code
xx
= Assembly Lot
PIN ASSIGNMENTS
SCL 1
GND 2
V_CC 3
TACH3 4
PWM2/ ₅
SMBALERT
TACH1 6
TACH2 7
PWM3 8
16 SDA
15 PWM1/XTO
ADT7473
TOP VIEW
14 V_CCP
13 D1+
12 D1–
11 D2+
10 D2–
9
TACH4/GPIO/THERM
SMBALERT
SCL 1
16 SDA
GND 2
15 PWM1/XTO
V_CC 3
14 V_CCP
TACH3/
ADDR SELECT
4
ADT7473−1 ¹³
D1+
THERM_LATCH/ ₅ TOP VIEW ₁₂ D1–
PWM2
TACH1 6
11 D2+
TACH2 7
PWM3/ADDREN 8
10 D2–
9
TACH4/GPIO/THERM
SMBALERT
© Semiconductor Components Industries, LLC, 2011
October, 2011 − Rev. 7
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 73 of this data sheet.
1
Publication Order Number:
ADT7473/D