LM95214CISD National Semiconductor, LM95214CISD Datasheet
LM95214CISD
Specifications of LM95214CISD
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LM95214CISD Summary of contents
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... Programmable digital filters and analog front end filter Connection Diagram Pentium ™ trademark of Intel Corporation. © 2007 National Semiconductor Corporation ■ 0.125°C LSb temperature resolution ■ 0.03125°C LSb remote temperature resolution with digital filter enabled ■ ...
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... Ordering Information Part Number LM95214CISD LM95214CISDX Simplified Block Diagram www.national.com Package NS Package Marking Number 95214CI SDA14B (LLP-14) 95214CI SDA14B (LLP-14) 2 Transport Media 1000 Units on Tape and Reel 4500 Units on Tape and Reel 30006102 ...
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... Fourth Diode Anode. Connected to remote discrete diode- connected transistor junction or to the diode-connected transistor junction on a remote IC whose die temperature is being sensed. A capacitor is not required between D4+ and D-. A 100 pF capacitor between D4+ and D- can be added and may improve performance in noisy systems. Float this pin if this thermal diode is not used ...
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Typical Application www.national.com 4 30006103 ...
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... Operating Ratings −0. 0.3V) DD ±1 mA (Notes 1, 5) ±5 mA Operating Temperature Range 30 mA Electrical Characteristics Temperature Range 10 mA LM95214CISD −65°C to +150°C Supply Voltage Range (V 2000V 200V = +3.0Vdc to 3.6Vdc. Boldface limits apply for T DD Conditions T = -40°C to +125°C, (Note +25°C to +85°C ...
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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 A J Symbol Parameter 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 LM95214 fully meet or exceed the published specifications of the SMBus version ...
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... Note 8: Local temperature accuracy does not include the effects of self-heating. The rise in temperature due to self-heating is the product of the internal power dissipation of the LM95214 and the thermal resistance. See Note 9: The accuracy of the LM95214CISD is guaranteed when using a typical MMBT3904 diode-connected transistor. For further information on other thermal diodes see applications Section 3.1 "Diode Non-ideality" or send email to hardware.monitor.team@national.com. ...
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... Functional Description LM95214 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 LM95214 can be used to very accurately mon- itor the temperature four external devices such as microprocessors, graphics processors or diode-connected 2N3904 transistor ...
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... POWER-ON-DEFAULT STATES LM95214 always powers up to these known default states. The LM95214 remains in these states until after the first con- version. 1. All Temperature readings set to 0°C until the end of the first conversion 2. Remote offset for all channels 0°C 3. Configuration: Active converting, Fault Queue enabled for Remote 3 and 4 4 ...
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... LM95214 incorporates a digital filter for Remote 1 and 2 Temperature Channels. When a filter is enabled the filtered readings are used for the TCRIT comparisons. There are two possible digital filter settings that are enabled through the Filter Setting Register at register address 0Fh ...
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... Configuration Register. When the fault queue is en- abled, the TCRIT1, TCRIT2 and TCRIT3 pins will be triggered if the temperature is above the Tcrit limit for 3 consecutive conversions and the corresponding mask bit the TCRIT Mask registers. Similarly the temperature needs to be below the Tcrit limit minus the hysteresis value for three consecutive www ...
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... LM95214's junction temper- ature to rise approximately 0.6°C and thus cause the Local temperature reading to shift. This can only be cancelled out if the environment that the LM95214 is enclosed in has stable and controlled air flow over the LM95214, as airflow can cause the thermal resistance to change dramatically ...
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... FIGURE 5. Temperature Comparison Logic and Status Register Simplified Diagram www.national.com 14 30006150 ...
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... Remote 2 Tcrit-1 Limit Register (Default Value 110° C) and Remote 2 Tcrit-2 Limit Register (Default Value = 85° C). When enabled, the remote temperature 3 is compared to the user programmable Remote 3 Tcrit Limit Register (Default 30006152 Value 85°C). The comparison result can trigger TCRIT1 pin, TCRIT2 pin or TCRIT3 pin depending on the settings in the TCRIT1 Mask, TCRIT2 Mask and TCRIT3 Mask Registers ...
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... The TCRIT response diagram of Figure 7 shows the local temperature interaction with the Tcrit limit and hysteresis val- ue. As can be seen in the diagram when the local temperature exceeds the Tcrit limit register value the LTn Status bit is set and the T_CRITn output(s) is/are activated. The Status bit(s) ...
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Serial Bus Write to the Internal Command Register (c) Serial Bus Read from a Register with the Internal Command Register preset to desired value. (d) Serial Bus Write followed by a Repeat Start and Immediate Read 1.12 SERIAL INTERFACE ...
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P0-P7: Command Register Name Local Temp MSB Local Temp LSB Remote Temp 1 MSB – Signed Remote Temp 1 LSB – Signed, Digital Filter Off Remote Temp 1 LSB – Signed, Digital Filter On Remote Temp 2 MSB – Signed ...
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... 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 after being read. If the user reads MSBs consecutively, each time the MSB is read, the LSB associated with that temperature will be locked in and override the previous LSB value locked ...
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... Remote Temp 3 MSB – Signed Remote Temp 3 LSB – Signed Remote Temp 4 MSB – Signed Remote Temp 4 LSB – Signed The Local temperature MSB value register range is +127°C to −128°C. The value programmed in this register is used to determine a local temperature error event. Bit(s) Bit Name ...
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... Remote Temperature Value Registers with Unsigned Format Register Name Remote Temp 1 MSB – Unsigned Remote Temp 1 LSB – Unsigned, Digital Filter Off Remote Temp 1 LSB – Unsigned, Digital Filter On Remote Temp 2 MSB – Unsigned Remote Temp 2 LSB – Unsigned, Digital Filter Off Remote Temp 2 LSB – ...
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Bit(s) Bit Name 7 SIGN 1/2 2.3 CONFIGURATION REGISTERS 2.3.1 Main Configuration Register Register Name Configuration Bit(s) Bit Name – STBY – 5–2 1 R4QE ...
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... Remote 3 temp conversion disabled Remote 2 Temperature Conversion Enable 1– Remote 2 temp conversion enabled 0– Remote 2 temp conversion disabled Remote 1 Temperature Conversion Enable 1– Remote 1 temp conversion enabled 0– Remote 1 temp conversion disabled Local Temperature Conversion Enable 1– Local temp conversion enabled 0– ...
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Bit(s) Bit Name – 7–4 3–2 R2F[1:0] 1–0 R1F[1:0] 2.3.5 1-Shot Register Name 1-Shot 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 7 BUSY 6 NR – 5–4 ...
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... Status 1 Register (Diode Fault) Status fault bits for open or shorted diode (i.e. Short Fault: D+ shorted to Ground or D-; Open Fault: D+ shorted to V During fault conditions the temperature reading is 0 °C if unsigned value registers are read or –128.000 °C if signed value registers are read. ...
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Status 2 (TCRIT1) Status bits for TCRIT1. When one or more of these bits are set and if not masked the TCRIT1 output will activate. TCRIT1 will deactivate when all these bits are cleared. Register Name Status 2 (TCRIT1) ...
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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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Status 4 (TCRIT3) Status bits for TCRIT3. When one or more of these bits are set and if not masked the TCRIT3 output will activate. TCRIT3 will deactivate when all these bits are cleared. Register Name Status 4 (TCRIT3) ...
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... Remote 4 Tcrit Mask: 1 – prevents the remote 4 temperature error event from propagating to the TCRIT2 pin 0 – allows the remote 4 temperature error event to propagate to the TCRIT2 pin Remote 3 Tcrit Mask: 1 – prevents the remote 3 temperature error event from propagating to the TCRIT2 pin 0 – ...
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... R2T2M R/W 1 R1T2M R/W 0 LTM R/W 2.6 LIMIT REGISTERS 2.6.1 Local Limit Register The Local Limit register range is 0°C to 127°C. The value programmed in this register is used to determine a local temperature error event. Register Name Local Tcrit Limit Bit(s) Bit Name ...
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... Remote 4 Tcrit Limit TCRIT3 Remote 4 Tcrit Limit 2.6.3 Common Tcrit Hysteresis Register The hysteresis register range is 0°C to 32°C. The value programmed in this register is used to modify all the limit values for decreasing temperature. Register Name Common Tcrit Hysteresis Bit(s) Bit Name ...
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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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... LM95214's pins. This presumes that the ambient air temperature is almost the same as the surface temperature of the printed circuit board; if the air temperature is much higher or lower than the surface temperature, the actual temperature of the LM95214 die will intermediate temperature between the surface and air temperatures ...
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... The bulk of the error caused by the 4.515 ohms will cause a positive offset in the temperature reading of 2.79°C wich can be cancelled out by setting the offset register to - 2.75°C. The spread in error cannot be canceled out ...
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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 transistor type. The LM95214 is calibrated ...
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... Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 14-Lead Molded Leadless Leadframe Package (LLP), Order Number LM95214CISD or LM95214CISDX NS Package Number SDA14B 36 ...
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Notes 37 www.national.com ...
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... National Semiconductor and the National Semiconductor logo are registered trademarks of National Semiconductor Corporation. All other brand or product names may be trademarks or registered trademarks of their respective holders. ...