ADT7461 Datasheet, PDF (1/20 Pages) Analog Devices – ±1°C Temperature Monitor with Series Resistance Cancellation

ADT7461
+15C Temperature Monitor
with Series Resistance
Cancellation
The ADT7461 is a dual-channel digital thermometer and under/over
temperature alarm intended for use in PCs and thermal management
systems. It is pin- and register-compatible with the ADM1032. The
ADT7461 has three additional features: series resistance cancellation
(where up to 3 kW (typical) of resistance in series with the temperature
monitoring diode may be automatically cancelled from the temperature
result, allowing noise filtering); configurable ALERT output; and an
extended, switchable temperature measurement range. The ADT7461
can accurately measure the temperature of a remote thermal diode to
±1°C and the ambient temperature to ±3°C. The temperature
measurement range defaults to 0°C to +127°C, compatible with the
ADM1032, but can be switched to a wider measurement range of −55°C
to +150°C. The ADT7461 communicates over a 2-wire serial interface
compatible with system management bus (SMBus) standards. An
ALERT output signals when the on-chip or remote temperature is out of
range. The THERM output is a comparator output that allows on/off
control of a cooling fan. The ALERT output can be reconfigured as a
second THERM output, if required.
The SMBus address of the ADT7461 is 0x4C. An ADT7461-2 is also
available, which uses SMBus Address 0x4D.
FEATURES
• On-Chip and Remote Temperature Sensor
• 0.25°C Resolution/1°C Accuracy on Remote Channel
• 1°C Resolution/3°C Accuracy on Local Channel
• Automatically Cancels Up to 3 kW (Typ) of Resistance in Series with
Remote Diode to Allow Noise Filtering
• Extended, Switchable Temperature Measurement Range
0°C to +127°C (Default) or –55°C to +150°C
• Pin− and Register−Compatible with the ADM1032
• 2−Wire SMBus Serial Interface with SMBus Alert Support
• Two SMBus Address Versions Available:
♦ ADT7461 SMBus Address is 0x4C
♦ ADT7461-2 SMBus Address is 0x4D
• Programmable Over/Undertemperature Limits
• Offset Registers for System Calibration
• Up to Two Overtemperature Fail−Safe THERM Outputs
• Small 8−Lead SOIC or 8−Lead MSOP Packages
• 170 mA Operating Current, 5.5 mA Standby Current
• These are Pb−Free Devices
APPLICATIONS
• Desktop and Notebook Computers
• Industrial Controllers
• Smart Batteries
• Embedded Systems
• Instrumentation
http://onsemi.com
MARKING
DIAGRAMS
8
1 _SOIC−8
CASE 751
8
ADT74
61A
#YWW
1
ADT7461A
#
Y
W
= Device Code
= Pb−Free Package
= Year
= Work Week
1
MSOP−8
CASE 846AB
8
T1x
AYWG
G
1
T1x = Refer to Order Info Table
A = Assembly Location
Y = Year
W = Work Week
G = Pb−Free Package
(Note: Microdot may be in either location)
PIN ASSIGNMENT
V_DD 1
D+ 2
D– 3
THERM 4
8 SCLK
7 SDATA
6 ALERT/THERM2
5 GND
(Top View)
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 18 of this data sheet.
© Semiconductor Components Industries, LLC, 2009
1
December, 2009 − Rev. 6
Publication Order Number:
ADT7461/D