Datasheet
Mobile Intel
®
Pentium
®
III Processor in BGA2 and Micro-PGA2 Packages at 1 GHz,
900 MHz, 850 MHz, 800 MHz, 750 MHz, 700 MHz, Low-voltage 750 MHz, Low-voltage
700 MHz, Low-voltage 600 MHz, Ultra Low-voltage 600 MHz and Ultra Low-voltage 500 MHz
283653-002 Datasheet 65
6.1 Thermal Diode
The mobile Pentium
III processor has an on-die thermal diode that can be used to monitor the die
temperature(T
J
). A thermal sensor located on the motherboard, or a stand-alone measurement kit,
may monitor the die temperature of the processor for thermal management or instrumentation
purposes. Table 34 and Table 35 provide the diode interface and specifications.
Note: The reading of the thermal sensor connected to the thermal diode will not necessarily reflect the
temperature of the hottest location on the die. This is due to inaccuracies in the thermal sensor, on-
die temperature gradients between the location of the thermal diode and the hottest location on the
die, and time based variations in the die temperature measurement. Time based variations can
occur when the sampling rate of the thermal diode (by the thermal sensor) is slower than the rate at
which the T
J
temperature can change.
Table 34. Thermal Diode Interface
Signal Name Pin/Ball Number Signal Description
THERMDA AA15 Thermal diode anode
THERMDC AB16 Thermal diode cathode
Table 35. Thermal Diode Specifications
Symbol Parameter Min Typ Max Unit Notes
I
FW
Forward Bias Current 5 500
µA
Note 1
n Diode Ideality Factor 1.0057 1.0080 1.0125 Notes 2, 3, 4
NOTES:
1. Intel does not support or recommend operation of the thermal diode under reverse bias. Intel does not
support or recommend operation of the thermal diode when the processor power supplies are not within
their specified tolerance range.
2. Characterized at 100°C.
3. Not 100% tested. Specified by design/characterization.
4. The ideality factor, n, represents the deviation from ideal diode behavior as exemplified by the diode
equation: Where I
s
= saturation current, q = electronic charge, V
d
= voltage across the diode, k =
Boltzmann Constant, and T = absolute temperature (Kelvin).
−⋅= 1
q
SFW
nkT
V
D
eII