Техническая Спецификация для Intel III M 866 MHz BXM80530B866512

 

 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 

85 

• 

A magnetically shielded inductor protects the circuit from picking up external flux noise.  This 
should provide better timing margins than with an unshielded inductor.   

• 

A discrete or routed resistor is required because the LC filter by nature has an under-damped 
response, which can cause resonance at the LC pole.  Noise amplification at this band, although 
not in the PLL-sensitive spectrum, could cause a fatal headroom reduction for analog circuitry.  
The resistor serves to dampen the response. Systems with tight space constraints should 
consider a discrete resistor to provide the required damping resistance. Too large of a damping 
resistance can cause a large IR drop, which means less analog headroom and lower frequency. 

• 

Ceramic capacitors have very high self-resonance frequencies, but they are not available in 
large capacitance values.  A high self-resonant frequency coupled with low ESL/ESR is crucial 
for sufficient rejection in the PLL and high frequency band.  The recommended tantalum 
capacitors have acceptably low ESR and ESL. 

• 

The capacitor must be close to the PLL1 and PLL2 pins, otherwise the value of the low ESR 
tantalum capacitor is wasted.  Note the distance constraint should be translated from the 0.1-

Ω

 

requirement. 

The mobile Pentium II processor LC filter cannot be used with the mobile Pentium III processor. 
The larger inductor of the old LC filter imposes a lower current rating. Due to increased current 

requirements for the mobile Pentium III processor, a lower value inductor is required.