Thermal Management—Processor

The ΨCA point at DTS = -1 defines the minimum ΨCA required at TDP considering the worst case system design TAMBIENT design point:

ΨCA = (TCASE-MAX – TAMBIENT-TARGET) / TDP

For example, for a 95 W TDP part, the Tcase maximum is 72.6 °C and at a worst case design point of 40 °C local ambient this will result in:

ΨCA = (72.6 – 40) / 95 = 0.34 °C/W

Similarly for a system with a design target of 45 °C ambient, the ΨCA at DTS = -1 needed will be 0.29 °C/W.

The second point defines the thermal solution performance (ΨCA) at TCONTROL. The following table lists the required ΨCA for the various TDP processors.

These two points define the operational limits for the processor for DTS 1.1

implementation. At TCONTROL the fan speed must be programmed such that the resulting ΨCA is better than or equivalent to the required ΨCA listed in the following

table. Similarly, the fan speed should be set at DTS = -1 such that the thermal

solution performance is better than or equivalent to the ΨCA requirements at TAMBIENT- MAX. The fan speed controller must linearly ramp the fan speed from processor DTS =

TCONTROL to processor DTS = -1.

Figure 16. Digital Thermal Sensor (DTS) 1.1 Definition Points

 

Intel® Xeon® Processor E3-1200 v3 Product Family

June 2013

Datasheet – Volume 1 of 2

Order No.: 328907-001

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