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TtmpturacutCStnsou
CC
ꢂT7408
FEATURES
FUN°TIONAL BLO°K DIAGRAM
V
12-bit temperature-to-digital converter
2ꢀ° accuracy
DD
8
DIGITAL COMPARATOR
12- / 10-Bit
–
+
EVENT#
7
DECIMATOR
Operation from −20ꢀ° to +125ꢀ°
Operation from 3 V to 3.6 V
TEMPERATURE
SENSOR
LPF
1-BIT
CAPABILITY
REGISTER
240 μA typical average supply current
Selectable 1.5ꢀ°, 3ꢀ°, 6ꢀ° hysteresis
SMBus-/I2°®-compatible interface
Dual-purpose event pin: comparator or interrupt
8-lead LF°SP_VD, 3 mm × 3 mm (JEDE° MO-229 VEED-4)
package
+
CONFIGURATION
REGISTER
–
REFERENCE
∑-∆
ALARM TEMP
UPPER
BOUNDARY TRIP
REGISTER
1-BIT
DAC
CLK
AND TIMING
GENERATION
ADDRESS
POINTER
REGISTER
ALARM TEMP
LOWER
BOUNDARY TRIP
REGISTER
°omplies with JEDE° standard J°-42.4 memory module
Thermal sensor component specification
MANUFACTURER’S
ID REGISTER
CRITICAL TEMP
REGISTER
ADT7408
FACTORY
RESERVED
REGISTER
TEMPERATURE
REGISTER
APPLI°ATIONS
Memory module temperature monitoring
Isolated sensors
Environmental control systems
°omputer thermal monitoring
Thermal protection
1
2
3
A0
A1
A2
5
6
SDA
SCL
SMBus/I²C INTERFACE
4
V
ss
Figure 1.
Industrial process control
Power system monitors
GENERAL DES°RIPTION
The ADT7408 is specified for operation at supply voltages from
3.0 V to 3.6 V. Operating at 3.3 V, the average supply current is
less than 240 μA typical. The ADT7408 offers a shutdown mode
that powers down the device and gives a shutdown current of 3 μA
typical. The ADT7408 is rated for operation over the −20°C to
+125°C temperature range. The ADT7408 is available in a lead-
free, 8-lead LFCSP_VD, 3 mm × 3 mm (JEDEC MO-229 VEED-4)
package.
The ADT7408 is the first digital temperature sensor that complies
with JEDEC standard JC-42.4 for the mobile platform memory
module. The ADT7408 contains a band gap temperature sensor
and a 12-bit ADC to monitor and digitize the temperature to a
resolution of 0.0625°C.
There is an open-drain EVENT# output that is active when the
monitoring temperature exceeds a critical programmable limit or
when the temperature falls above or below an alarm window.
This pin can operate in either comparator or interrupt mode.
There are three slave device address pins that allow up to eight
ADT7408s to be used in a system that monitors temperature of
various components and subsystems.
Rev. 0
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responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
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