Mobile Intel Pentium 4 Processor with 533 MHz Front Side Bus

Mobile Intel

Pentium

4 Processor with 533 MHz System Bus Datasheet 17

Electrical Specifications

NOTES:

1. Diagram not to scale.

2. No specification for frequencies beyond fcore (core frequency).

3. fpeak, if existent, should be less than 0.05 MHz.

2.4.3 Catastrophic Thermal Protection

The mobile Intel Pentium 4 processor supports the THERMTRIP# signal for catastrophic thermal

protection. Alternatively, an external thermal sensor can 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 135°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. Refer to

Section 4.2 for more details on THERMTRIP#.

Figure 2. Phase Lock Loop (PLL) Filter Requirements

0 dB

-28 dB

-34 dB

0.2 dB

forbidden

zone

-0.5 dB

forbidden

zone

1 MHz 66 MHz

core

pea

1 HzDC

passband

high frequency

band