Dts 1.1 A New Fan Speed Control Algorithm Without Tambient Data - Intel 2ND GENERATION CORE PROCESSOR FAMILY DESKTOP - THERMAL MECHANICAL SPECIFICATIONS AND DESIGN GUIDELINES 01-2011 Specifications

Sensor Based Thermal Specification Design Guidance
8.4.3 DTS 1.1 A New Fan Speed Control Algorithm without
T
AMBIENT
In most system designs incorporating processor ambient inlet data in fan speed control
adds design and validation complexity with a possible BOM cost impact to the system.
A new fan speed control methodology is introduced to improve system acoustics
without needing the processor inlet ambient information.
The DTS 1.1 implementation consists of two parts, a 
a  point at DTS = -1.
CA
The 
CA
worst case system design Tambient design point:
For example, for a 95 TDP part, the Tcase max is 72.6C and at a worst case design
point of 40C local ambient this will result in
Similarly for a system with a design target of 45 C ambient the
will be 0.29 C/W.
The second point defines the thermal solution performance (
Table 8-1
These two points define the operational limits for the processor for DTS 1.1
implementation. At T
is better than or equivalent to the required

CA
speed should be set at DTS = -1 such that the thermal solution performance is better
than or equivalent to the
temperature, the fan speed controller must linearly change the fan speed from DTS =
T
CONTROL
DTS 1.1.
Thermal/Mechanical Specifications and Design Guidelines
Data
point at DTS = -1 defines the minimum
 = (T
CA
 = (72.6 - 40) / 95 = 0.34 C/W
CA
lists the required 
CA
the fan speed must be programed such that the resulting
CONTROL
requirements at Tambient_Max. Based on the processor

CA
to DTS = -1 between these points.
CA
required at TDP considering the

CA
- T ) / TDP
CASE_max Ambient target
for various TDP processors.
listed in

CA
Figure 8-8
requirement at T
CONTROL
 at DTS = -1
CA
) at T .
CA CONTROL
Table 8-1. Similarly the fan
gives a visual description on
and
needed
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