se97b NXP Semiconductors, se97b Datasheet - Page 10

• Manufacturer Part Number: se97b
• Description: Ddr Memory Module Temp Sensor With Integrated Spd
• Manufacturer: NXP Semiconductors

NXP Semiconductors
SE97B_1
Product data sheet
7.3.3.1 Comparator mode
7.3.3.2 Interrupt mode
7.3.3.3 Switching between Comparator mode and Interrupt mode
7.3.3 EVENT operation modes
In comparator mode, the EVENT output behaves like a window-comparator output that
asserts when the temperature is outside the window (e.g., above the value programmed in
the Upper Boundary Alarm Trip register or below the value programmed in the Lower
Boundary Alarm Trip register or above the Critical Alarm Trip register if T
selected). Reads/writes on these registers do not affect the EVENT output in comparator
mode. The EVENT signal remains asserted until the temperature goes inside the alarm
window or the window thresholds are reprogrammed so that the current temperature is
within the alarm window.
The comparator mode is useful for thermostat-type applications, such as turning on a
cooling fan or triggering a system shutdown when the temperature exceeds a safe
operating range.
In interrupt mode, EVENT asserts whenever the temperature crosses an alarm window
threshold. After such an event occurs, writing a 1 to the clear event bit in the configuration
register de-asserts the EVENT output until the next trigger condition occurs.
In interrupt mode, EVENT asserts when the temperature crosses the alarm upper
boundary. If the EVENT output is cleared and the temperature continues to increase until
it crosses the critical temperature threshold, EVENT asserts again. Because the
temperature is greater than the critical temperature threshold, a clear event command
does not clear the EVENT output. Once the temperature drops below the critical
temperature, EVENT de-asserts immediately.
If the EVENT output is not cleared before or when the temperature is in the critical
temperature threshold, EVENT will remain asserted after the temperature drops below the
critical temperature until a clear event command.
When the part is in Comparator mode and the temperature windows are set such that the
BAW bit is set and the EVENT pin asserted (EventOutputControl = 1) and the part is
switched to Interrupt mode, the EVENT is de-asserted.
Rev. 01 — 27 January 2010
DDR memory module temp sensor with integrated SPD
© NXP B.V. 2010. All rights reserved.
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