lm95245eb National Semiconductor Corporation, lm95245eb Datasheet
lm95245eb
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lm95245eb Summary of contents
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... Targeted for Intel 45nm processor diodes ■ Two Formats: −128°C to +127.875°C and 0°C to 255.875°C Connection Diagram TruTherm™ trademark of National Semiconductor Corporation. Intel® registered trademark of Intel Corporation. Pentium® registered trademark of Intel Corporation. © 2007 National Semiconductor Corporation ■ ...
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Ordering Information Package Order Number Marking LM95245CIMM T45C LM95245CIMM-1 T46C LM95245CIMMX T45C LM95245CIMMX-1 T46C Simplified Block Diagram www.national.com NS Package Number Transport Media MUA08A (MSOP-8) 1000 Units on Tape and Reel MUA08A (MSOP-8) 1000 Units on Tape and Reel MUA08A ...
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Pin Descriptions Pin Name Type Number V 1 Power Analog Input/Output Positive input from the thermal diode Analog Input/Output Negative input from the thermal diode. 4 T_CRIT Digital Output 5 GND Ground 6 OS/A0 Digital ...
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Absolute Maximum Ratings Supply Voltage Voltage at SMBDAT, SMBCLK, T_CRIT, OS/A0 Pins Voltage at Other Pins Input Current at D− Pin (Note 4) Input Current at All Other Pins (Note 4) Output Sink Current SMBDAT, T_Crit, OS Pins ...
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Logic Electrical Characteristics Digital DC Characteristics Unless otherwise noted, these specifications apply for all other limits +25°C, unless otherwise noted MAX Symbol SMBDAT, SMBCLK INPUTS V Logical “1” Input Voltage IN(1) ...
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SMBus Digital Switching Characteristics Unless otherwise noted, these specifications apply for V Boldface limits apply for The switching characteristics of the LM95245 fully meet or exceed the published specifications of the SMBus version ...
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Notes Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is guaranteed to be functional, but do not guarantee specific performance limits. For guaranteed specifications and ...
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Typical Performance Characteristics Thermal Diode Capacitor or PCB Leakage Current Effect Remote Diode Temperature Reading Conversion Rate Effect on Average Power Supply Current www.national.com Remote Temperature Reading Sensitivity to Thermal Diode Filter Capacitance, TruTherm Enabled 30015105 Intel Processor on 45nm ...
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Functional Description The LM95245 is a temperature sensor that measures Local and Remote temperature zones. The LM95245 uses a ΔV temperature sensing method. A differential voltage, repre- senting temperature, is digitized using a Sigma-Delta analog to digital converter. TruTherm ...
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Configuration Register 1 defaults to 00h. This sets the LM95245 as follows: A. The STOP/RUN defaults to the active/converting mode. B. The Local and Remote TCRIT and OS Masks are reset to 0. 10. Configuration Register 2 defaults to ...
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Figure 3 shows the filter in use in a typical Intel processor on a 45/65/90 nm process system. Note that the two curves have been purposely offset for clarity. Inserting the filter does not induce an offset as shown. FIGURE ...
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Temperature Digital Output Binary +125°C 0111 1101 0000 0000 +25°C 0001 1001 0000 0000 +1°C 0000 0001 0000 0000 +0.125°C 0000 0000 0010 0000 0°C 0000 0000 0000 0000 −0.125°C 1111 1111 1110 0000 ...
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COMMUNICATING with the LM95245 (a) Serial Bus Write to the Internal Command Register (b) Serial Bus Write to the internal Command Register followed by a Data Byte (c) Serial Bus byte Read from a Register with the internal Command ...
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The data registers in the LM95245 are selected by the Com- mand Register. At power-up the Command Register is set to “00”, the location for the Read Local Temperature Register. The Command Register latches the last location it was set ...
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LM95245 Registers Command register selects which registers will be read from or written to. Data for this register should be transmitted during the Command Byte of the SMBus write communication. POR means Power-On Reset. P0-P7: Command P7 Read Register ...
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Read Register Name Address (Hex) IDENTIFICATION REGISTERS Manufacturer ID 0xFE Revision ID 2.1 LOCAL and REMOTE MSB and LSB TEMPERATURE REGISTERS (Read Only Address 00h) 10-bit plus sign format: BIT Value Temperature Data: LSb = 1°C. (Read Only Address 30h) ...
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Only Address 31h) 13-bit unsigned format: BIT Value Temperature Data: LSb = 1°C. (Read Only Address 32h) 13-bit unsigned binary formats with filter on: BIT Value (Read Only Address 32h) 13-bit unsigned binary formats with filter off: BIT Value ...
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Address 11h) 10-bit plus sign format: BIT Value Power up default is 00h. (R/W Address 12h) 10-bit plus sign format: BIT Value Power up default is 00h. LSb = 0.125 °C. 2.3 GENERAL CONFIGURATION REGISTERS (Read/write Address 03h/09h or ...
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Power up default is 02h (1 second). (Write Only Address 0Fh): Writing to this register will start one conversion if the device is in standby mode (i.e. STOP/RUN bit = 1). 2.4 STATUS REGISTERS (Read Only Address 02h ...
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Address 19h 128 64 Power on Reset default is 6Eh (110°C). (Read/Write Address 21h Power on Reset default is 0Ah (10°C). 2.6 IDENTIFICATION REGISTERS (Read Only Address FEh): Always returns 01h ...
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In the active region, the -1 term is negligible and may be elim- inated, yielding the following equation In Equation 2, η and I are dependant upon the process that S was used in the fabrication of the particular diode. ...
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Solving Equation 6 for R equal to ±1.73Ω results in the PCB additional error due to the spread in the series resistance of ±1.07°C. The spread in error cannot be canceled out would require measuring each individual thermal ...
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Physical Dimensions inches (millimeters) unless otherwise noted 8-Lead Molded Mini-Small-Outline Package (MSOP), Order Number LM95245CIMM, LM95245CIMMX, LM95245CIMM-1, LM95245CIMMX-1 JEDEC Registration Number MO-187 NS Package Number MUA08A 23 www.national.com ...
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