Intel 500 - DATASHEET REV 003, Техническое описание

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Thermal Specifications
64 Datasheet
NOTES:
1.
Intel does not support or recommend operation of the thermal diode under reverse bias.
2. Same as I
FW
in Table 19 .
3. Characterized across a temperature range of 50-100°C.
4. Not 100% tested. Specified by design characterization.
5. The ideality factor, n
Q
, represents the deviation from ideal diode behavior as exemplified
by the equation for the collector current:
I
C
=I
s
*(e
(qV
BE
/n
Q
kT)
-1)
where I
S
= saturation current, q = electronic charge, V
BE
= voltage across the transistor
base emitter junction (same nodes as VD), k = Boltzmann Constant, and T = absolute
temperature (Kelvin).
6. The series resistance, R
T
, provided in the Diode Model Table ( Table 19 ) can be used for
more accurate readings as needed.
When calculating a temperature based on the thermal diode measurements, a number
of parameters must be either measured or assumed. Most devices measure the diode
ideality and assume a series resistance and ideality trim value, although are capable of
also measuring the series resistance. Calculating the temperature is then accomplished
using the equations listed under Table 19 . In most sensing devices, an expected value
for the diode ideality is designed-in to the temperature calculation equation. If the
designer of the temperature sensing device assumes a perfect diode, the ideality value
(also called n
trim
) is 1.000. Given that most diodes are not perfect, the designers
usually select an n
trim
value that more closely matches the behavior of the diodes in
the processor. If the processor diode ideality deviates from that of the n
trim,
each
calculated temperature is offset by a fixed amount. This temperature offset can be
calculated with the equation:
T
error(nf)
= T
measured
* (1 - n
actual
/n
trim
)
Where T
error(nf)
is the offset in degrees C, T
measured
is in Kelvin, n
actual
is the measured
ideality of the diode, and n
trim
is the diode ideality assumed by the temperature
sensing device.
5.2 Intel® Thermal Monitor
The Intel Thermal Monitor helps control the processor temperature by activating the
TCC (Thermal Control Circuit) when the processor silicon reaches its maximum
operating temperature. The temperature at which the Intel Thermal Monitor activates
the TCC is not user configurable. Bus traffic is snooped in the normal manner and
interrupt requests are latched (and serviced during the time that the clocks are on)
while the TCC is active.
With a properly designed and characterized thermal solution, it is anticipated that the
TCC would only be activated for very short periods of time when running the most
power intensive applications. The processor performance impact due to these brief
periods of TCC activation is expected to be minor and hence not detectable.
Table 20. Thermal Diode Parameters using Transistor Model
Symbol Parameter Min Typ Max Unit Notes
I
FW
Forward Bias Current 5 200 µA
1, 2
I
E
Emitter Current 5 200 µA
1
n
Q
Transistor Ideality 0.997 1.001 1.005
3, 4, 5
Beta 0.3 0.760
3, 4
R
T
Series Resistance 2.79 4.52 6.24 Ω
3, 6