Intel 520J - Pentium 4 2.80GHz 800MHz 1MB Socket 775 CPU, Datasheet

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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 co12 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.