Intel 5400 Series Fan Power Supply, Fan Specifications Boxed 4-wire PWM/DTS Heatsink Solution

Thermal/Mechanical Reference Design

Clearance is required around the heatsink to ensure unimpeded airflow for proper cooling. The physical baseboard keepout requirements for the active solution are the same as the passive CEK solution shown in Appendix B. Refer to Figure B-18through Figure B-20for additional details on the active CEK thermal solution volumetrics.

2.5.8.1Fan Power Supply

The active heatsink includes a fan, which requires a +12 V power supply. Platforms must provide a matched fan power header to support the boxed processor. Table 2-9contains specifications for the input and output signals at the heatsink fan connector.

The fan outputs a SENSE signal, an open-collector output, which pulses at a rate of two pulses per fan revolution. A baseboard pull-up resistor provides VCC to match the baseboard-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.

It is recommended that a 4 pin fan header be used on the baseboard, in addition to, a control ASIC that can send a PWM signal to the active fan heatsink solution on the 4th pin, at a nominal 25 KHz frequency. If a 3-pin CPU fan header is used instead, the active fan heatsink solution will revert back to an automatic ambient air temperature control mode.

The fan power header on the baseboard must be positioned to allow the fan heatsink power cable to reach it. The fan power header identification and location must be documented in the supplier’s platform documentation, or on the baseboard itself. The baseboard fan power header should be positioned within 177.8 mm [7 in.] from the center of the processor socket.

Table 2-9. Fan Specifications (Boxed 4-wire PWM/DTS Heatsink Solution)

Description	Min	Typ	Max	Max	Unit	Notes
		Steady	Steady	Startup
+12V: 12 Volt Fan Power	10.8	12	12	13.2	V
Supply
IC: Fan Current Draw	N/A	1.25	1.5	1.5	A
SENSE: SENSE Frequency	2	2	2	2	Pulses per fan revolution	1

Note: System board should pull this pin up to VCC with a resistor.

Figure 2-27. Fan Cable Connection (Active CEK)

50 Quad-Core Intel® Xeon® Processor 5400 Series TMDG