LM95235CIMM National Semiconductor, LM95235CIMM Datasheet
LM95235CIMM
Specifications of LM95235CIMM
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LM95235CIMM Summary of contents
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... Features n Remote and Local temperature channels n Diode Model Selection Bit - MMBT3904 or 65/90 nm processor diodes Connection Diagram TruTherm ™ trademark of National Semiconductor Corporation. Intel ® registered trademark of Intel Corporation. Pentium ® registered trademark of Intel Corporation. Intel ® ...
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... Ordering Information Package NS Package Order Code Marking T36C LM95235CIMM T36C LM95235CIMMX T36D LM95235DIMM T36D LM95235DIMMX T36E LM95235EIMM T36E LM95235EIMMX Simplified Block Diagram www.national.com Transport Media Number MUA08A 1000 Units on Tape and Reel (MSOP-8) MUA08A 3500 Units on Tape and Reel (MSOP-8) MUA08A ...
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Pin Descriptions Pin Name Type Number 1 V Power Analog Input/Output 3 D- Analog Input/Output 4 T_CRIT Digital Output 5 GND Ground 6 OS/A0 Digital Input/Output 7 SMBDAT Digital Input/Output 8 SMBCLK Digital Input Typical Application Function ...
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... Intel Processor MMBT3904 MMBT3904 11 0.125 13 0.03125 11 0.125 63 33 350 300 4 -40˚C to +125˚C ≤ MIN A 0˚C ≤ T LM95235CIMM A -40˚C ≤ T LM95235DIMM A -40˚C ≤ T LM95235EIMM A ) +3.0V to +3. the junction temperature of the LM95235 LM95235 LM95235 LM95235 CIMM DIMM ...
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Temperature-to-Digital Converter Characteristics Unless otherwise noted, these specifications apply for V ≤ T ≤ all other limits T MIN A MAX A is the junction temperature of the remote thermal diode. Parameter D− Source Voltage High-level External ...
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Logic Electrical Characteristics SMBus Digital Switching Characteristics Unless otherwise noted, these specifications apply for V 80 pF. Boldface limits apply for T switching characteristics of the LM95235 fully meet or exceed the published specifications of the SMBus version 2.0. The ...
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Logic Electrical Characteristics 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 ...
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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 ∆V temperature sensing method. A differential voltage, repre- senting temperature, is digitized using a Sigma-Delta analog to digital converter. TruTherm ...
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Functional Description 7. Remote TCRIT limit default is 6Eh (110 ˚C). 8. Remote Offset High and Low bytes default to 00h. 9. Configuration Register 1 defaults to 00h. This sets the LM95235 as follows: A. The STOP/RUN defaults to ...
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Functional Description 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 ...
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Functional Description 1.6 SMBDAT OPEN-DRAIN OUTPUT The SMBDAT output is an open-drain output and does not have internal pull-ups. A “high” level will not be observed on this pin until pull-up current is provided by some external source, typically ...
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Functional Description tively, each time the MSB is read, the LSB associated with that temperature will be locked in and override the previous LSB value locked-in. (a) Serial Bus Write to the Internal Command Register (b) Serial Bus Write ...
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Functional Description 1.11 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 protocol. This may ...
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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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LM95235 Registers 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) 10-bit plus sign format: BIT Value Temperature Data: LSb ...
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LM95235 Registers For data synchronization purposes, the MSB register should be read first if the user wants to read both MSB and LSB registers. The LSB will be locked after the MSB is read. The LSB will be unlocked ...
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LM95235 Registers 2.3 GENERAL CONFIGURATION REGISTERS (Read/write Address 03h/09h or 09h/03h STOP/RUN 0 Remote T_CRIT Mask Remote OS Mask Bits Power up default is 00h. (Read/write Address ...
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LM95235 Registers 2.4 STATUS REGISTERS (Read Only Address 02h Busy 0 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 ...
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... IDENTIFICATION REGISTERS (Read Only Address FEh): Always returns 01h (Read Only Address FFh): Default is B1h. This register will increment by 1 every time there is a revision to the die by National Semiconductor. The initial revision bits for B1h are shown below www.national.com (Continued) ...
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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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Applications Hints 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 topol- ogy. 3.1.2 Calculating Total System Accuracy The ...
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... Compensating for Different Non-Ideality In order to compensate for the errors introduced by non- ideality, 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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Applications Hints 9. Leakage current between D+ and GND and between D+ and D− should be kept to a minimum. Thirteen nano- amperes of leakage can cause as much as 0.2˚C of error in the diode temperature reading. Keeping ...
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... Molded Mini-Small-Outline Package (MSOP), Order Number LM95235CIMM, LM95235DIMM, LM95235EIMM, LM95235CIMMX, LM95235DIMMX, LM95235EIMMX National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. ...