LM95231_06 NSC [National Semiconductor], LM95231_06 Datasheet
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LM95231_06
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LM95231_06 Summary of contents
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LM95231 Precision Dual Remote Diode Temperature Sensor with SMBus Interface and TruTherm General Description The LM95231 is a precision dual remote diode temperature sensor (RDTS) that uses National’s TruTherm technology. The 2-wire serial interface of the LM95231 is compatible with ...
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Ordering Information Package Part Number Marking LM95231BIMM T23B MUA08A (MSOP-8) LM95231BIMMX T23B MUA08A (MSOP-8) LM95231BIMM-1 T25B MUA08A (MSOP-8) LM95231BIMMX-1 T25B MUA08A (MSOP-8) LM95231BIMM-2 T26B MUA08A (MSOP-8) LM95231BIMMX-2 T26B MUA08A (MSOP-8) LM95231CIMM T23C MUA08A (MSOP-8) LM95231CIMMX T23C MUA08A (MSOP-8) LM95231CIMM-1 T25C ...
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Pin Descriptions (Continued) Label Pin # D1− 2 D2+ 3 D2− 4 GND SMBDAT 7 SMBCLK 8 Simplified Block Diagram Function Diode Return Current Sink To Diode Cathode. A capacitor is not required between D1+ and ...
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Absolute Maximum Ratings Supply Voltage Voltage at SMBDAT, SMBCLK Voltage at Other Pins Input Current at All Pins (Note 2) Package Input Current (Note 2) SMBDAT Output Sink Current Junction Tempeature (Note 3) Storage Temperature ESD Susceptibility (Note 4) Human ...
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Temperature-to-Digital Converter Characteristics Unless otherwise noted, these specifications apply for V ≤T ≤ all other limits MIN A MAX A junction temperature of the remote thermal diode. Parameter Diode Source Current Power-On Reset Threshold Logic ...
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Logic Electrical Characteristics SMBus Digital Switching Characteristics Unless otherwise noted, these specifications apply for V pF. Boldface limits apply for characteristics of the LM95231 fully meet or exceed the published specifications of the SMBus version 2.0. ...
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Logic Electrical Characteristics Pin Label Circuit # 1 D1 D1− D2 D2− GND SMBDAT C 8 SMBCLK C Note 3: Thermal resistance junction-to-ambient when attached to ...
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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 1.0 Functional Description The LM95231 is a digital sensor that can sense the tempera- ture of 3 ...
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Functional Description the remote diodes to sense temperatures above 127˚C. Local temperature resolution is not programmable and is always 9-bits plus sign and has a 0.25˚C LSb. The LM95231 remote diode temperature accuracy will be trimmed for the thermal ...
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Functional Description 1.4 TEMPERATURE DATA FORMAT Temperature data can only be read from the Local and Remote Temperature registers . Remote temperature data with the digital filter off is repre- sented by an 11-bit, two’s complement word or unsigned ...
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Functional Description 1.7 COMMUNICATING with the LM95231 The data registers in the LM95231 are selected by the Command Register. At power-up the Command Register is set to “00”, the location for the Read Local Temperature Register. The Command Register ...
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Functional Description (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 Register preset ...
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Functional Description 1.8 SERIAL INTERFACE RESET In the event that the SMBus Master is RESET while the LM95231 is transmitting on the SMBDAT line, the LM95231 must be returned to a known state in the communication protocol. This may ...
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LM95231 Registers 2.1 STATUS REGISTER (Read Only Address 02h Busy 0 Bits Name 7 Busy 6-4 Reserved 3 Remote 2 TruTherm Mode Enabled (R2TME) 2 Remote 1 TruTherm Mode Enabled (R2TME) 1 Remote Diode 2 Missing (RD2M) ...
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LM95231 Registers 2.3 REMOTE DIODE FILTER CONTROL REGISTER (Read/write Address 06h Bits Name 7-3 Reserved 2 Remote 2 Filter Enable (R2FE) 1 Reserved 0 Remote 1 Filter Enable (R1FE) Power up default is 05h. ...
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LM95231 Registers Bits Description 2-0 R1M2:R1M0 Power up default is 01h. 2.6 LOCAL and REMOTE MSB and LSB TEMPERATURE REGISTERS (Read Only Address 10h) 9-bit plus sign format: BIT Value Temperature Data: LSb = 1˚C. (Read Only Address 20h) ...
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LM95231 Registers 2.7 MANUFACTURERS ID REGISTER (Read Address FEh) The default value is 01h. 2.8 DIE REVISION CODE REGISTER (Read Address FFh) The default value is A1h. This register will increment by 1 every time there is a revision ...
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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 3, because Equation (5) only applies to this topol- ogy. 3.1.2 Calculating Total System Accuracy The ...
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Applications Hints supporting the MMBT3904 transistor and the Pentium 4 processor on 90nm process without the requirement for additional trims. For most accurate measurements TruTherm mode should be turned on when measuring the Pentium 4 processor on the 90nm ...
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Physical Dimensions inches (millimeters) unless otherwise noted 8-Lead Molded Mini-Small-Outline Package (MSOP), Order Number LM95231BIMM, LM95231BIMMX, LM95231BIMM-1, LM95231BIMMX-1, LM95231BIMM-2, LM95231CIMM, LM95231CIMMX, LM95231CIMM-1, LM95231CIMMX-1, LM95231CIMM-2 or LM95231CIMMX-2 National does not assume any responsibility for use of any circuitry described, no circuit ...