Intel Core™2 Extreme Processor QX6800 (8M Cache, 2.93 GHz, 1066 MHz FSB) HH80562XH0778M Data Sheet

Product codes

HH80562XH0778M

Datasheet

Electrical Specifications

This chapter describes the electrical characteristics of the processor interfaces and

signals. DC electrical characteristics are provided.

2.1

Power and Ground Lands

The processor has VCC (power), VTT and VSS (ground) inputs for on-chip power

distribution. All power lands must be connected to V

, while all VSS lands must be

connected to a system ground plane. The processor V

lands must be supplied the

voltage determined by the Voltage IDentification (VID) lands.

The signals are denoted as V

, which provide termination for the front side bus and

power to the I/O buffers. A separate supply must be implemented for these lands, that

meets the V

specifications outlined in

Table 4

2.2

Decoupling Guidelines

Due to its large number of transistors and high internal clock speeds, the processor is

capable of generating large current swings. This may cause voltages on power planes

to sag below their minimum specified values if bulk decoupling is not adequate. Larger

bulk storage (C

BULK

), such as electrolytic or aluminum-polymer capacitors, supply

current during longer lasting changes in current demand by the component, such as

coming out of an idle condition. Similarly, they act as a storage well for current when

entering an idle condition from a running condition. The motherboard must be designed

to ensure that the voltage provided to the processor remains within the specifications

listed in

Table 4

. Failure to do so can result in timing violations or reduced lifetime of

the component.

2.2.1

Decoupling

regulator solutions need to provide sufficient decoupling capacitance to satisfy the

processor voltage specifications. This includes bulk capacitance with low effective series

resistance (ESR) to keep the voltage rail within specifications during large swings in

load current. In addition, ceramic decoupling capacitors are required to filter high

frequency content generated by the front side bus and processor activity. Consult the

Voltage Regulator-Down (VRD) 11.0 Processor Power Delivery Design Guidelines For

Desktop LGA775 Socket.

2.2.2

Decoupling

Decoupling must be provided on the motherboard. Decoupling solutions must be sized

to meet the expected load. To insure compliance with the specifications, various factors

associated with the power delivery solution must be considered including regulator

type, power plane and trace sizing, and component placement. A conservative

decoupling solution would consist of a combination of low ESR bulk capacitors and high

frequency ceramic capacitors. FSB Decoupling

The processor integrates signal termination on the die. In addition, some of the high

frequency capacitance required for the FSB is included on the processor package.

However, additional high frequency capacitance must be added to the motherboard to

properly decouple the return currents from the front side bus. Bulk decoupling must

also be provided by the motherboard for proper [A]GTL+ bus operation.