LM95234_07 NSC [National Semiconductor], LM95234_07 Datasheet
LM95234_07
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LM95234_07 Summary of contents
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LM95234 Quad Remote Diode and Local Temperature Sensor with SMBus Interface and TruTherm™ Technology General Description LM95234 is an 11-bit digital temperature sensor with a 2-wire System Management Bus (SMBus) interface that can very accurately monitor the temperature of four ...
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Ordering Information Part Number LM95234CISD LM95234CISDX Simplified Block Diagram www.national.com Package NS Package Marking Number 95234CI SDA14B (LLP-14) 95234CI SDA14B (LLP-14) 2 Transport Media 1000 Units on Tape and Reel 4500 Units on Tape and Reel 20106302 ...
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Pin Descriptions Label Pin # Connect V 2 Positive Supply Voltage Input DD D4+ 3 Diode Current Source D3+ 4 Diode Current Source D− 5 Diode Return Current Sink D2+ 6 Diode Current Source D1+ 7 Diode ...
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Typical Application www.national.com 4 20106303 ...
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Absolute Maximum Ratings Supply Voltage Voltage at SMBDAT, SMBCLK, TCRIT1, TCRIT2, TCRIT3 Voltage at Other Pins D− Input Current Input Current at All Other Pins (Note 2) Package Input Current (Note 2) SMBDAT, TCRIT1, TCRIT2, TCRIT3 Output Sink Current Storage ...
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Parameter Power-On Reset Threshold TCRIT1 Pin Temperature Threshold TCRIT2 Pin Temperature Threshold TCRIT3 Pin Temperature Threshold Logic Electrical Characteristics DIGITAL DC CHARACTERISTICS Unless otherwise noted, these specifications apply for V ; all other limits =+25°C, unless otherwise ...
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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 LM95234 fully meet or exceed the published specifications of the SMBus version ...
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Pin # Label D4 D2+ 7 D1+ 8 GND TCRIT1 11 TCRIT2 12 SMBDAT 13 SMBCLK 14 TCRIT2 Note 3: Reflow temperature profiles are different for ...
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Typical Performance Characteristics Conversion Rate Effect on Average Power Supply Current Remote Temperature Reading Sensitivity to Thermal Diode Filter Capacitance, TruTherm Disabled Intel Processor Process Process Thermal Diode Performance Comparison Thermal Diode Capacitor or ...
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Functional Description LM95234 is an 11-bit digital temperature sensor with a 2-wire System Management Bus (SMBus) interface that can monitor the temperature of four remote diodes as well as its own tem- perature. The LM95234 can be used to ...
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FIGURE 1. Conversion Rate Effect on Power Supply Current 1.2 POWER-ON-DEFAULT STATES LM95234 always powers up to these known default states. The LM95234 remains in these states until after the first con- version. 1. All Temperature readings set to 0°C ...
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Seventeen and fifty degree step response FIGURE 3. Digital Filter Response in a typical Intel processor process. The filter curves were purposely offset for clarity. Figure 3 shows the filter in ...
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Temperature Digital Output Binary +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 −1°C 1111 1111 0000 0000 −25°C 1110 0111 0000 0000 −55°C 1100 1001 0000 0000 11-bit, ...
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FIGURE 5. Temperature Comparison Logic and Status Register Simplified Diagram www.national.com 14 20106350 ...
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TCRIT1 Mask Register, Status Register 1 and 2, and TCRIT1 output logic diagram. b) TCRIT2 Mask Register, Status Register 1 and 3, and TCRIT2 output logic diagram. c) TCRIT3 Mask Register, Status Register 1 and 4, and 20106351 TCRIT3 ...
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Limit assignments for each TCRIT output pin: TCRIT1 TCRIT2 Remote 4 Remote 4 Remote 4 Tcrit Limit Tcrit Limit Remote 3 Remote 3 Remote 3 Tcrit Limit Tcrit Limit Remote 2 Remote 2 Remote 2 Tcrit-1 Limit Tcrit-2 Limit Remote ...
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Serial Bus Write to the internal Command Register followed by a the Data Byte (b) Serial Bus Write to the Internal Command Register (c) Serial Bus Read from a Register with the Internal Command Register preset to desired value. ...
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SMBCLK or SMBDAT lines must be held low for at least 35ms. 2. When SMBDAT is HIGH, have the master initiate an SMBus start. The LM95234 will respond properly to ...
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Register Name Command Remote Temp 4 LSB – Unsigned Diode Model Select Remote 1 Offset Remote 2 Offset Remote 3 Offset Remote 4 Offset Configuration Conversion Rate Channel Conversion Enable Filter Setting 1-shot Common Status Register Status 1 (Diode Fault) ...
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Bit(s) Bit Name 7 SIGN Bit(s) Bit Name 7 1/2 6 1/4 5 1/8 4-0 0 2.1.2 Remote Temperature Value Registers with Signed Format Register Name ...
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Bit(s) Bit Name Read/ Write 1/ 2.1.3 Remote Temperature Value Registers with Unsigned Format Register Name Remote Temp 1 ...
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DIODE CONFIGURATION REGISTERS 2.2.1 Diode Model Select Register Name Diode Model Select Bit(s) Bit Name 7 R4TE 3 R3TE 2 R2TE 1 R1TE 0 0 2.2.2 Remote 1-4 Offset Register Name Remote 1 Offset Remote 2 Offset ...
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Bit(s) Bit Name Read/ Write – STBY R/W – 5– R4QE R/W 0 R3QE R/W 2.3.2 Conversion Rate Register Register Name Conversion Rate Bit(s) Bit Name Read/ Write – 7-2 RO 1-0 CR[1:0] R/W 2.3.3 ...
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Bit(s) Bit Name Read/ Write – 7– R4CE R/W 3 R3CE R/W 2 R2CE R/W 1 R1CE R/W 0 LCE R/W 2.3.4 Filter Setting Register Name Filter Setting Bit(s) Bit Name – 7–4 3–2 R2F[1:0] 1–0 R1F[1:0] 2.3.5 ...
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Bit(s) Bit Name 7–0 - 2.4 STATUS REGISTERS 2.4.1 Common Status Register Register Name Common Status Register Bit(s) Bit Name Read/ Write 7 BUSY – 5– SR4F RO 2 SR3F RO 1 SR2F RO ...
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Bit(s) Bit Name Read/ Write 4 R3DS RO 3 R2DO RO 2 R2DS RO 1 R1DO RO 0 R1DS RO 2.4.3 Status 2 (TCRIT1) Status bits for TCRIT1. When one or more of these bits are set and if not ...
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Status 3 (TCRIT2) Status bits for TCRIT2. When one or more of these bits are set and if not masked the TCRIT2 output will activate. TCRIT2 will deactivate when all these bits are cleared. Register Name Status 3 (TCRIT2) ...
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Bit(s) Bit Name Read/ Write 7– R4T3 RO 3 R3T3 RO 2 R2T3 RO 1 R1T3 RO 0 LT3 RO 2.4.6 Diode Model Status Register Name Diode Model Status (TruTherm on and 3904 connected) Bit(s) Bit Name ...
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MASK REGISTERS 2.5.1 TCRIT1 Mask Register The mask bits in this register allow control over which error events propagate to the TCRIT1 pin. Register Name TCRIT1 Mask Bit(s) Bit Name Read/ Write – 7 R4TM R/W 3 ...
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TCRIT3 Mask Register The mask bits in this register allow control over which error events propagate to the TCRIT3 pin. Register Name TCRIT3 Mask Bit(s) Bit Name Read/ Write – 7 R4TM R/W 3 R3TM R/W 2 ...
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Register Name Remote 1 Tcrit-1 Limit (used by TCRIT1 error events) Remote 2 Tcrit-1 Limit (used by TCRIT1 error events) Remote 3 Tcrit Limit (used by TCRIT1, TCRIT2 and TCRIT3 error events) Remote 4 Tcrit Limit (used by TCRIT1, TCRIT2 ...
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Bit(s) Bit Name 2.7 IDENTIFICATION REGISTERS Register Name Manufacturer ID Revision ID www.national.com Read/ Description Write R/W bit weight 2°C R/W bit weight 1°C Command Read Byte Write (Hex) 0xFE 0xFF ...
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Applications Hints The LM95234 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 9, because Equation 5 only applies to this topology. 3.1.2 Calculating Total System Accuracy The voltage seen by the ...
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Pentium M 1.00151 1.00220 1.00289 (Centrino) MMBT3904 1.003 AMD Athlon MP 1.002 1.008 model 6 AMD Athlon 64 1.008 1.008 AMD Opteron 1.008 1.008 AMD Sempron 1.00261 3.1.3 Compensating for Different Non-Ideality In order to compensate for the errors introduced ...
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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 inches (millimeters) unless otherwise noted 14-Lead Molded Leadless Leadframe Package (LLP), Order Number LM95234CISD or LM95234CISDX NS Package Number SDA14B 37 www.national.com ...
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THE CONTENTS OF THIS DOCUMENT ARE PROVIDED IN CONNECTION WITH NATIONAL SEMICONDUCTOR CORPORATION (“NATIONAL”) PRODUCTS. NATIONAL MAKES NO REPRESENTATIONS OR WARRANTIES WITH RESPECT TO THE ACCURACY OR COMPLETENESS OF THE CONTENTS OF THIS PUBLICATION AND RESERVES THE RIGHT TO MAKE ...