N270 datasheet(23/57 Pages) INTEL

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Electrical Specifications

Datasheet

3.4

Catastrophic Thermal Protection

The processor supports the THERMTRIP# signal for catastrophic thermal protection.

An external thermal sensor should also be used to protect the processor and the

system against excessive temperatures. Even with the activation of THERMTRIP#,

which halts all processor internal clocks and activity, leakage current can be high

enough such that the processor cannot be protected in all conditions without the

removal of power to the processor. If the external thermal sensor detects a

catastrophic processor temperature of 125°C (maximum), or if the THERMTRIP#

signal is asserted, the VCC supply to the processor must be turned off within 500 ms

to prevent permanent silicon damage due to thermal runaway of the processor.

THERMTRIP# functionality is not ensured if the PWRGOOD signal is not asserted.

3.5

Reserved and Unused Pins

All other RSVD signals can be left as No Connect. Connection of these pins to VCC, VSS,

or to any other signal (including each other) can result in component malfunction or

incompatibility with future processors. See Section 4.2 for a pin listing of the

processor and the location of all RSVD pins.

For reliable operation, always connect unused inputs or bidirectional signals to an

appropriate signal level. Unused active low AGTL+ inputs may be left as no connects if

AGTL+ termination is provided on the processor silicon. Unused active high inputs

should be connected through a resistor to ground (VSS). Unused outputs can be left

unconnected.

3.6

FSB Frequency Select Signals (BSEL [2:0])

The BSEL [2:0] signals are used to select the frequency of the processor input clock

(BCLK [1:0]). These signals should be connected to the clock chip and the appropriate

chipset on the platform. The BSEL encoding for BCLK [1:0] is shown in Table 4.

Table 4. BSEL [2:0] Encoding for BCLK Frequency

BSEL [2]

BSEL [1]

BSEL [0]

BCLK Frequency

133 MHz

N270 Datasheet(PDF) 23 Page - Intel Corporation