LM95172EWG10A NSC [National Semiconductor], LM95172EWG10A Datasheet

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Digital Temp Sensor with 3-Wire Interface General Description The LM95172EWG is an integrated digital-output tempera- ture sensor with a Serial Peripheral Interface (SPI) and MI- CROWIRE™-compatible interface in a 10-pin Cerpack high temperature ceramic package. It ...

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Pin Descriptions Pin Name Type Number 1 OVERTEMP Output 2 SC Input Input 5 GND Ground 6 NC Bidirectio 7 SI Power DD ANALOG V 10 Power DD IO Simplified Block Diagram ...

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Typical Application FIGURE 1. Microcontroller Interface - normal connection 30076603 3 www.national.com ...

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Absolute Maximum Ratings V and V Supply DD ANALOG DD IO Voltages Voltage at any Pin Input Current at any Pin Storage Temperature Soldering Information Infrared or Convection (20 sec.) ESD Susceptibility (Note 7) Human Body Model Machine Model Charged ...

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Parameter Conditions T = −40°C to 140°C A Power-On Reset T = −40°C to 175°C A Threshold T = −40°C to 200°C A LM95172EWG Typical Limits (Note 3) (Note 2) 0.9 2.1 0.8 2.1 0.3 2.1 5 Units (Limit) V ...

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Logic Electrical Characteristics Digital DC Characteristics Unless otherwise noted, these specifications apply for -40°C to 200°C; all other limits T A Symbol Parameter V Logical "1" Input Voltage IH V Logical "0" Input Voltage IL V Digital ...

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Serial Bus Digital Switching Characteristics Unless otherwise noted, these specifications apply for V lines = 100 pF unless otherwise specified. Boldface limits apply for T otherwise noted. Symbol t SC (Serial Clock) Period (Chip Select) Low to ...

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Note 1: “Absolute Maximum Ratings” indicate limits beyond which damage to the device may occur, including inoperability and degradation of device reliability and/or performance. Functional operation of the device and/or non-degradation at the Absolute Maximum Ratings or other conditions beyond ...

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TRI-STATE Test Circuit 1.0 Functional Description The LM95172EWG temperature sensor incorporates a tem- perature sensor and a 13-bit to 16-bit ΣΔ ADC (Sigma-Delta Analog-to-Digital Converter). Compatibility LM95172EWG's three wire serial interface with SPI and MI- FIGURE 8. LM95172EWG Functional Block ...

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INITIAL SOFTWARE RESET AND POWER-UP SEQUENCES AND POWER ON RESET (POR) 1.1.1 Software Reset Sequence A software reset sequence must be followed, after the initial V and V supply voltages reach their specified DD ANALOG DD IO minimum operating ...

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ONE SHOT CONVERSION The LM95172EWG features a one-shot conversion bit, which is used to initiate a singe conversion and comparison cycle when the LM95172EWG is in shutdown mode. While the LM95172EWG is in shutdown mode, writing a "1" to ...

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COMMUNICATING WITH THE LM95172EWG The serial interface consists of three lines: CS (Chip Select), SC (Serial Clock), and the bi-directional SI/O (Serial I/O) data line. A high-to-low transition of the CS line initiates the com- munication. The master (processor) ...

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TEMPERATURE DATA FORMAT Temperature data is represented by a 13- to 16-bit, two's complement word with a Least Significant Bit (LSB) equal to 13-Bit Resolution. First Bit (D15) is Sign, the last bit (D0) is Toggle and bits D1 ...

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Resolution. First bit (D15) is Sign and the last bit (D0) is Toggle. Temperature +175°C +150°C +80°C +25°C +0.015625°C 0°C −0.015625°C −40°C 16-Bit Resolution. First bit (D15) is Sign and the last bit (D0) is the LSB. Temperature +175°C ...

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INTERNAL REGISTER STRUCTURE The LM95172EWG has four registers that are accessible by issuing a command byte (a R/W Bit plus the register address: Control/ Status and Identification. Which of these registers will be read or ...

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When in 16-Bit resolution mode, this is the Least Significant Bit of the temperature data. Reset Conditions: See Sections 1.1.1 through 1.1.3 for reset conditions. One-Shot State: 8000h (-256°C) 1.7.3 Control/Status Register (Read/Write) Pointer Address: 81h (Read); 01h (Write) D15 ...

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Control/Status Register (Continued) Bit <5:4>: Temperature Resolution Bits. Selects one of four user-programmable temperature data resolutions as indicated in the following table. Bit <3>: Always write a zero to this Bit. Bit <2:1>: Reserved Bits. Will return whatever was last ...

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MFGID: Manufacturer, Product, and Step ID Register (Read Only) Pointer Address: 87h D15 D14 Bit <15:8>: Manufacturer Identification Byte. Always returns 80h to uniquely identify the manufacturer as National Semiconductor Corporation. Bit <7:4>: Product Identification ...

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Typical Applications FIGURE 13. Temperature monitor using Intel 196 processor FIGURE 14. LM95172EWG digital input control using microcontroller's general purpose I/O. 30076620 30076619 19 www.national.com ...

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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 10-pin Cerpack Package LM95172EWG 20 ...

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Notes 21 www.national.com ...

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