LM95235EVAL/NOPB National Semiconductor, LM95235EVAL/NOPB Datasheet

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... TruTherm BJT beta compensation technology ■ LM95235Q is AEC-Q100 Grade 3 compliant and is manufactured on an Automotive Grade Flow Connection Diagram TruTherm™ trademark of National Semiconductor Corporation. Intel® registered trademark of Intel Corporation. Pentium® registered trademark of Intel Corporation. © 2008 National Semiconductor Corporation ■ ...

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Ordering Information Packag Order Code Markin g T36C LM95235CIMM T36C LM95235CIMMX T36D LM95235DIMM T36D LM95235DIMMX T36E LM95235EIMM T36E LM95235EIMMX 36QE LM95235QEIMM 36QE LM95235QEIMMX Simplified Block Diagram www.national.com e NS Package Transport Media Number MUA08A 1000 Units on Tape and Reel ...

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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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Parameter SMBus Inactive conversion rate (Note 11) Quiescent Current Standby Mode D− Source Voltage High-level External Diode Current Source Low-level Diode Source Current Ratio Power-On Reset Voltage T_CRIT Pin Temperature Default Threshold OS Pin Temperature Default Threshold Logic ...

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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 LM95235 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 20174905 Intel Processor on 65nm ...

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Functional Description The LM95235 is a temperature sensor that measures Local and Remote temperature zones. The LM95235 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 LM95235 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. Digital Filter Response in a typical Intel processor process. The filter curves were purposely offset for clarity. 1.5 TEMPERATURE DATA FORMAT Temperature data can only be read from the Local and ...

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Level Output Current with the supply voltage at 3.0V kΩ (5%) or 88.7 kΩ (1%). 1.7 T_CRIT OUTPUT AND TCRIT LIMIT The LM95235's T_CRIT pin is an active-low open-drain out- put that is triggered when the local and/or ...

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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 Register preset to desired value. ...

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SERIAL INTERFACE RESET In the event that the SMBus Master is RESET while the LM95235 is transmitting on the SMBDAT line, the LM95235 must be returned to a known state in the communication pro- tocol. This may be done ...

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LM95235 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 www.national.com Write No. POR Read/ Address of Default Write (Hex) bits (Hex) 0x01 0xFF 0xB1 16 Description RO Always returns 0x01 RO Returns revision number. ...

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LOCAL and REMOTE MSB and LSB TEMPERATURE REGISTERS (Read Only Address 00h) 10-bit plus sign format: BIT Value SIGN Temperature Data: LSb = 1°C. (Read Only Address 30h) 10-bit plus sign format: BIT Value Temperature Data: LSb = 0.125°C. ...

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Only Address 32h) 13-bit unsigned binary formats with filter off: BIT Value Temperature Data: LSb = 0.125°C filter off or 0.03125°C filter on. For data synchronization purposes, the MSB register should be read first if the user wants to ...

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GENERAL CONFIGURATION REGISTERS (Read/write Address 03h/09h or 09h/03h STOP/RUN 0 Remote T_CRIT Mask Bits Power up default is 00h. (Read/write Address 04h/0Ah or 0Ah/04h):2-bit format: BIT D7 ...

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STATUS REGISTERS (Read Only Address 02h Busy 0 Bits Name 7 Busy 6-5 Reserved 4 ROS 3 Reserved 2 Diode Fault 1 RTCRIT 0 LOC (Read Only Address 33h): D7 Not Ready TruTherm 3904 Detect Bits ...

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Address 21h Power on Reset default is 0Ah (10°C). 2.6 IDENTIFICATION REGISTERS (Read Only Address FEh): Always returns 01h (Read Only Address FFh): Default is B1h. This register will increment by ...

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Applications Hints The LM95235 can be applied easily in the same way as other integrated-circuit temperature sensors, and its remote diode sensing capability allows used in new ways as well. It can be soldered to a ...

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TruTherm should only be enabled when measuring the tem- perature of a transistor integrated as shown in the processor of Figure 7, because Equation 5 only applies to this topology. 3.1.2 Calculating Total System Accuracy The voltage seen by the ...

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... Compensating for Different Non-Ideality In order to compensate for the errors introduced by non-ide- ality, the temperature sensor is calibrated for a particular processor. National Semiconductor temperature sensors are always calibrated to the typical non-ideality and series resis- tance of a given processor type. The LM95235 is calibrated ...

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SMBus maximum frequency of communication is rather low (100 kHz max), care still needs to be taken to ensure proper termination within a system with multiple parts on the bus and long printed circuit board traces lowpass ...

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Physical Dimensions Order Number LM95235CIMM, LM95235DIMM, LM95235EIMM, LM95235QEIMM, LM95235CIMMX, LM95235DIMMX, www.national.com inches (millimeters) unless otherwise noted 8-Lead Molded Mini-Small-Outline Package (MSOP), JEDEC Registration Number MO-187 LM95235EIMMX, and LM95235QEIMMX, NS Package Number MUA08A 26 ...

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Notes 27 www.national.com ...

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