STTS2002(2011) View Datasheet(PDF) - STMicroelectronics

Part Name

Description

MFG CO.

STTS2002
(Rev.:2011)

2.3 V memory module temperature sensor with a 2 Kb SPD EEPROM

STMicroelectronics

STTS2002 Datasheet PDF : 52 Pages

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STTS2002

Temperature sensor registers

Table 9. Configuration register bit definitions (continued)

Bit

Definition

Hysteresis enable (see Figure 8 and Table 10)

– 00 = Hysteresis is disabled (default)

– 01 = Hysteresis is enabled at 1.5 °C

– 10 = Hysteresis is enabled at 3 °C

10:9 – 11 = Hysteresis is enabled at 6 °C

Hysteresis applies to all limits when the temperature is dropping below the threshold so that once the

temperature is above a given threshold, it must drop below the threshold minus the hysteresis in order to be

flagged as an interrupt event. Note that hysteresis is also applied to the EVENT pin functionality. When

either of the lock bits is set, these bits cannot be altered.

15:11

Reserved for future use. These bits will always read ‘0’ and writing to them will have no effect. For

future compatibility, all RFU bits must be programmed as ‘0’.

1. As this device is used in DIMM (memory modules) applications, it is strongly recommended that only the active-low polarity

(default) is used. This will provide full compatibility with the STTS424E02. This is the recommended configuration for the

STTS2002.

2. The actual incident causing the event can be determined from the read temperature register. Interrupt events can be

cleared by writing to the clear event bit (writing to this bit will have no effect on overall device functioning).

3. Writing to this register has no effect on overall device functioning in comparator mode. When read, this bit will always

return a logic '0' result.

Figure 8. Hysteresis

TH - HYS

TL - HYS

Below Window bit

Above Window bit

AI12270

1. TH = Value stored in the alarm temperature upper boundary trip register

2. TL = Value stored in the alarm temperature lower boundary trip register

3. HYS = Absolute value of selected hysteresis

Table 10. Hysteresis as applied to temperature movement

Below alarm window bit

Above alarm window bit

Sets

Clears

Temperature slope

Falling

Rising

Temperature

threshold