se97pw/1 NXP Semiconductors, se97pw/1 Datasheet - Page 7

• Manufacturer Part Number: se97pw/1
• Description: Se97 Memory Module Temp Sensor With Integrated Spd
• Manufacturer: NXP Semiconductors

NXP Semiconductors
SE97_2
Product data sheet
7.3.2 Critical trip
7.4 Conversion rate
7.5 Power-up default condition
7.6 Device initialization
The device can be programmed in such a way that the EVENT output is triggered when
the temperature exceeds the critical trip point set by the Critical Alarm Trip register (04h).
When the temperature sensor reaches the critical temperature value, the device is
automatically placed in comparator mode; the EVENT output is only cleared when the
temperature falls below the critical temperature value and cannot be cleared through the
clear EVENT bit or SMBus ALERT.
The conversion time is the amount of time required for the ADC to complete a temperature
measurement for the local temperature sensor. The conversion rate is the inverse of the
conversion period which describes the number of cycles the temperature measurement
completes in one second—the faster the conversion rate, the faster the temperature
reading is updated. The SE97’s conversion rate is at least 8 Hz or 125 ms.
After power-on, the SE97 is initialized to the following default condition:
SE97 temperature sensors have programmable registers, which, upon power-up, default
to zero. The open-drain EVENT output is default to being disabled, comparator mode and
active LOW. The alarm trigger registers default to being unprotected. The configuration
registers, upper and lower alarm boundary registers and critical temperature window are
defaulted to zero and need to be programmed to the desired values. SMBus TIMEOUT
feature defaults to being enabled and can be programmed to disable. These registers are
required to be initialized before the device can properly function. Except for the SPD,
which does not have any programmable registers, and does not need to be initialized.
Table 3
registers.
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Starts monitoring local sensor
EVENT register is cleared; EVENT output is pulled HIGH by external pull-ups
EVENT hysteresis is defaulted to 0 C
Command pointer is defaulted to ‘00h’
Critical Temp, Alarm Temperature Upper and Lower Boundary Trip register are
defaulted to 0 C
Capability register is defaulted to ‘0015h’ for the C-grade and to ‘0017h’ for the
B-grade
Operational mode: comparator
SMBus register is defaulted to ‘00h’
shows the default values and the example value to be programmed to these
Rev. 02 — 12 October 2007
Memory module temp sensor with integrated SPD
© NXP B.V. 2007. All rights reserved.
SE97
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