ADT7476A_16 Datasheet, PDF (1/69 Pages) ON Semiconductor – Remote Thermal Controller and Voltage Monitor

ADT7476A
Remote Thermal Controller
and Voltage Monitor
The ADT7476A controller is a thermal monitor and multiple PWM
fan controller for noise-sensitive or power-sensitive applications
requiring active system cooling. The ADT7476A can drive a fan using
either a low or high frequency drive signal and can monitor the
temperature of up to two remote sensor diodes plus its own internal
temperature. The part also measures and controls the speed of up to
four fans, so the fans operate at the lowest possible speed for minimum
acoustic noise.
The automatic fan speed control loop optimizes fan speed
for a given temperature. The effectiveness of the system’s thermal
solution can be monitored using the THERM input. The ADT7476A
also provides critical thermal protection to the system using the
bidirectional THERM pin as an output to prevent system or
component overheating.
Features
• Monitors Up to Five Voltages
• Improved TACH and PWM Performance
• Controls and Monitors Up to Four Fans
• High and Low Frequency Fan Drive Signal
• One On-Chip and Two Remote Temperature Sensors
• Extended Temperature Measurement Range Up to 191°C
• 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^® 4 Processor
• Thermal Control Circuit via THERM Input
• 3-wire and 4-wire Fan Speed Measurement
• Limit Comparison of All Monitored Values
• 5.0 V Support on all TACH and PWM Channels
• Meets SMBus 2.0 Electrical Specifications
• This Device is Pb-Free, Halogen Free and is RoHS Compliant
www.onsemi.com
QSOP−24 NB
CASE 492B
PIN ASSIGNMENT
SDA 1
24 PWM1/XTO
SCL 2
GND 3
V_CC 4
VID0/GPIO0 5
VID1/GPIO1 6
VID2/GPIO2 7
VID3/GPIO3 8
ADT7476A
(Top View)
23 V_CCP
22 +2.5V_IN/THERM
21 +12V_IN/VID5
20 +5V_IN
19 VID4/GPIO4
18 D1+
17 D1−
TACH3 9
PWM2/
10
SMBALERT
TACH1 11
16 D2+
15 D2−
14 *
TACH2 12
13 PWM3/ADDREN
*TACH4/THERM/SMBALERT/GPIO6/ADDR SELECT
MARKING DIAGRAMS
ADT7476AARQZ
#YYWW
xxxx
ADT7476AARQZ = Specific Device Code
#
= Pb-Free Package
YYWW
= Date Code
xxxx
= Assembly Lot Code
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 68 of this data sheet.
© Semiconductor Components Industries, LLC, 2016
1
February, 2016 − Rev. 7
Publication Order Number:
ADT7476A/D