Sun Microsystems SME5224AUPA-400 manual Thermal Deﬁnitions and Speciﬁcations

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UltraSPARC™-II CPU Module	Advanced Version
400 MHz CPU, 4.0 MB E-Cache	SME5224AUPA-400

Thermal Deﬁnitions and Speciﬁcations

Term	Deﬁnition	Speciﬁcation	Comments
Tj	Maximum device	85 °C,	The Tj can't be measured directly by a thermo-couple
	junction		probe. It must always be estimated as Tj or less. Less is
	temperature		preferred.

Tc	Maximum case	76.7 °C	Measurable at the top-center of the device. Requires a hole
	temperature		in the base of the heatsink to allow the thermocouple to be
			in contact with the case. Maximum case temperature is
			speciﬁed using a CPU device at its maximum power
			dissipation.

Ts	Heatsink	75 °C	Measurable at the temperature of the base of the heatsink.
	temperature		The best approach is to embed a thermocouple in a cavity
			drilled in the heatsink base. An alternative approach is to
			place the thermocouple between the ﬁns/pins of the heat-
			sink (insulated from the airﬂow) and in contact with the
			base plate of the heatsink.

Ta	Module ambient air	see page 20	The air temperature as it approaches the heatsink.
	temperature

Pd	Typical power	19.0 W	The worst case compute loads over the entire process
	dissipation of the		range.
	CPU

θjc	Maximum	0.5°C/W	The speciﬁcation for the UltraSPARC™–II, 400 MHz CPU
	junction-to-case		in a ceramic LGA package.
	thermal resistance
	of the package

θcs	Case-to-heatsink	0.1 °C/W	Accuracy of this value requires that good thermal contact is
	thermal resistance		made between the package and the heatsink.

θsa	Heatsink-to-air	see page 20	This value is dependent on the heatsink design, the airﬂow
	thermal resistance		direction, and the airﬂow velocity.

Va	Air velocity	see page 20	The ducted airﬂow.

July 1999

Sun Microsystems, Inc

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Contents Performance Module Features Module BeneﬁtsModule Description Ease of System DesignUltraSPARC-II CPU CPU Features CPU BeneﬁtsCPU Description UltraSPARC-II Data Buffer UDB-II Data Buffer DescriptionExternal Cache Description Module Component Overview Block DiagramUPA Interconnect UPA Connector PinsSystem Interface Jtag Interface Module PowerModule ID Clock Interface Signal DescriptionSignal Type Name and Function System InterfaceInitialization Interface Miscellaneous SignalsJTAG/Debug Interface Tested CPU to UPA Module ClocksSystem Clocks System Clock DistributionClock Signal Distribution Absolute Maximum Ratings Electrical CharacteristicsSymbol Parameter Rating Units Symbol Parameter Min Typ Max UnitsSymbol Parameter Conditions Min Typ Max Units DC CharacteristicsModule Power Consumption Module System Loading Example for UPADATA, Upaecc UPA Data Bus Spice ModelClock Buffers Setup and Hold Time SpeciﬁcationsUpaclk Module Clocks Cpuclk Module ClockMin Max Unit Propagation Delay, Output Hold Time SpeciﬁcationsTiming Measurement Waveforms CPU Module Components Mechanical SpecificationsCPU Module Side View Two Step Approach to Thermal Design Thermal SpecificationsTerm Deﬁnition Speciﬁcation Comments Thermal Deﬁnitions and SpeciﬁcationsAir Velocity Temperature Estimating and Measuring MethodsAirﬂow Cooling Measurement Method Air Velocity SpeciﬁcationsHeatsink Temperature Measuring Method Case Temperature Measuring MethodJtag Testability AC Characteristics Jtag TimingMHz CPU MHz TCK Symbol Parameter Signals Conditions Jtag Ieee 1149.1 Timing Pin UPA Connector PIN Assignments TOP ViewVddcore GND Vddcore GND Vddcore UPAPORTID1 UPA Connector PIN Assignments Bottom ViewValue Parameter Conditions Min Typ Storage and Shipping SpecificationHandling CPU Modules Date Document No Change Ordering InformationDocument Revision History Part Number CPU Speeds DescriptionSun Microsystems, Inc UltraSPARC -II CPU Module UltraSPARC-II CPU Data Buffer Description Block Diagram System Interface Module ID System Interface JTAG/Debug Interface UPA and CPU Clocks Clock Signal Distribution Absolute Maximum Ratings DC Characteristics UPA Data Bus Spice Model Upaclk Module Clocks Propagation Delay, Output Hold Time Speciﬁcations Mechanical Specifications CPU Module Side View Two Step Approach to Thermal Design Thermal Deﬁnitions and Speciﬁcations Temperature Estimating and Measuring Methods Case Temperature Measuring Method AC Characteristics Jtag Timing Jtag Ieee 1149.1 Timing UPA Connector PIN Assignments TOP View UPA Connector PIN Assignments Bottom View Storage and Shipping Specification Ordering Information Sun Microsystems, Inc