NEC Intel Xeon E5-2420 N8101-571F User Manual

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Intel® Xeon® Processor E5-1600/E5-2600/E5-4600 Product Families

Datasheet Volume One

PECI is an Intel proprietary interface that provides a communication channel between 

Intel processors and chipset components to external system management logic and 

thermal monitoring devices. The processor contains a Digital Thermal Sensor (DTS) 
that reports a relative die temperature as an offset from Thermal Control Circuit (TCC) 

activation temperature. Temperature sensors located throughout the die are 
implemented as analog-to-digital converters calibrated at the factory. PECI provides an 

interface for external devices to read processor temperature, perform processor 

manageability functions, and manage processor interface tuning and diagnostics. 
Please refer to 

processor specific implementation details for PECI. 

The PECI interface operates at a nominal voltage set by V

TTD

. The set of DC electrical 

specifications shown in 

is used with devices normally operating from a V

TTD

 

interface supply.

The PECI client and host input buffers must use a Schmitt-triggered input design for 

improved noise immunity. Please refer to 

.

The processor core, processor uncore, Intel® QuickPath Interconnect link, PCI 

Express* and DDR3 memory interface frequencies) are generated from BCLK{0/1}_DP 

and BCLK{0/1}_DN signals. There is no direct link between core frequency and Intel 
QuickPath Interconnect link frequency (for example, no core frequency to Intel 

QuickPath Interconnect multiplier). The processor maximum core frequency, Intel 

QuickPath Interconnect link frequency and DDR memory frequency are set during 
manufacturing. It is possible to override the processor core frequency setting using 

software. This permits operation at lower core frequencies than the factory set 

maximum core frequency.

Minimum V

P

Maximum V

P

Minimum V

N

Maximum V

N

PECI High Range

PECI Low Range

Valid Input
Signal Range

Minimum
Hysteresis

V

TTD

PECI Ground