Intel 521 Data Sheet - Page 92

92

Datasheet

Boxed Processor Specifications

The fan heatsink outputs a SENSE signal that is an open-collector output that pulses at a rate of

2 pulses per fan revolution. A baseboard pull-up resistor provides V

OH

to match the system board-

mounted fan speed monitor requirements, if applicable. Use of the SENSE signal is optional. If the

SENSE signal is not used, pin 3 of the connector should be tied to GND.

The fan heatsink receives a PWM signal from the motherboard from the 4th pin of the connector

labeled as CONTROL.

The boxed processor's fan heatsink requires a constant +12 V supplied to pin 2 and does not

support variable voltage control or 3-pin PWM control.

The power header on the baseboard must be positioned to allow the fan heatsink power cable to

reach it. The power header identification and location should be documented in the platform

documentation, or on the system board itself.

Figure 7-6

shows the location of the fan power

connector relative to the processor socket. The baseboard power header should be positioned

within 110 mm [4.33 inches] from the center of the processor socket.

Figure 7-5. Boxed Processor Fan Heatsink Power Cable Connector Description

Table 7-1. Fan Heatsink Power and Signal Specifications

Description

Min

Typ

Max

Unit

Notes

+12 V: 12 volt fan power supply

10.2

12

13.8

V

-

IC:

Peak Fan current draw

Fan start-up current draw

Fan start-up current draw maximum duration

—

1.1

—

—

1.5

2.2

1.0

A

A

Second

-

SENSE: SENSE frequency

—

2

—

pulses per fan

revolution

1

NOTES:

1.

Baseboard should pull this pin up to 5V with a resistor.

CONTROL

21

25

28

kHz

2, 3

2.

Open drain type, pulse width modulated.

3.

Fan will have pull-up resistor to 4.75 V maximum of 5.25 V.

Boxed_Proc_PwrCable

Pin

Signal

1

2

3

4

1

2

3

4

GND

+12 V

SENSE

CONTROL

Straight square pin, 4-pin terminal housing with

polarizing ribs and friction locking ramp.

0.100" pitch, 0.025" square pin width.

Match with straight pin, friction lock header on

mainboard.

Section	Page
Contents	3
Revision History	7
Intel® Pentium® 4 Processors 570/571, 560/561, 550/551, 540/541, 530/531, and 520/521	9
1 Introduction	11
1.1 Terminology	12
1.1.1 Processor Packaging Terminology	12
1.2 References	13
2 Electrical Specifications	15
2.1 FSB and GTLREF	15
2.2 Power and Ground Lands	15
2.3 Decoupling Guidelines	15
2.3.1 VCC Decoupling	16
2.3.2 FSB GTL+ Decoupling	16
2.3.3 FSB Clock (BCLK[1:0]) and Processor Clocking	16
2.4 Voltage Identification	17
2.4.1 Phase Lock Loop (PLL) Power and Filter	19
2.5 Reserved, Unused, FC and TESTHI Signals	20
2.6 FSB Signal Groups	21
2.7 GTL+ Asynchronous Signals	22
2.8 Test Access Port (TAP) Connection	23
2.9 FSB Frequency Select Signals (BSEL[2:0])	23
2.10 Absolute Maximum and Minimum Ratings	24
2.11 Processor DC Specifications	24
2.12 VCC Overshoot Specification	33
2.12.1 Die Voltage Validation	33
2.13 GTL+ FSB Specifications	34
3 Package Mechanical Specifications	35
3.1 Package Mechanical Drawing	35
3.2 Processor Component Keep-Out Zones	39
3.3 Package Loading Specifications	39
3.4 Package Handling Guidelines	39
3.5 Package Insertion Specifications	40
3.6 Processor Mass Specification	40
3.7 Processor Materials	40
3.8 Processor Markings	40
3.9 Processor Land Coordinates	41
4 Land Listing and Signal Descriptions	43
4.1 Processor Land Assignments	43
4.2 Alphabetical Signals Reference	66
5 Thermal Specifications and Design Considerations	75
5.1 Processor Thermal Specifications	75
5.1.1 Thermal Specifications	75
5.1.2 Thermal Metrology	79
5.2 Processor Thermal Features	79
5.2.1 Thermal Monitor	79
5.2.2 Thermal Monitor 2	80
5.2.3 On-Demand Mode	81
5.2.4 PROCHOT# Signal	82
5.2.5 THERMTRIP# Signal	82
5.2.6 TCONTROL and Fan Speed Reduction	82
5.2.7 Thermal Diode	83
6 Features	85
6.1 Power-On Configuration Options	85
6.2 Clock Control and Low Power States	85
6.2.1 Normal State	86
6.2.2 HALT and Enhanced HALT Powerdown States	86
6.2.2.1 HALT Powerdown State	86
6.2.2.2 Enhanced HALT Powerdown State	86
6.2.3 Stop-Grant State	87
6.2.4 Enhanced HALT Snoop or HALT Snoop State, Grant Snoop State	88
6.2.4.1 HALT Snoop State, Grant Snoop State	88
6.2.4.2 Enhanced HALT Snoop State	88
7 Boxed Processor Specifications	89
7.1 Mechanical Specifications	90
7.1.1 Boxed Processor Cooling Solution Dimensions	90
7.1.2 Boxed Processor Fan Heatsink Weight	91
7.1.3 Boxed Processor Retention Mechanism and Heatsink Attach Clip Assembly	91
7.2 Electrical Requirements	91
7.2.1 Fan Heatsink Power Supply	91
7.3 Thermal Specifications	93
7.3.1 Boxed Processor Cooling Requirements	93

Intel 521 Data Sheet - Page 92

Boxed Processor Fan Heatsink Power Cable Connector Description, Table 7-1. Fan Heatsink

Page 92 highlights