STEVAL-IFS003V1 STMicroelectronics, STEVAL-IFS003V1 Datasheet

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Digital temperature sensor and thermal watchdog Features ■ Measures temperatures from –55°C to +125°C (–67°F to +257°F) – 0.5 C (typ) accuracy ± ° – (max) accuracy from ± ° ■ Low operating current: 125 µA (typ) ■ ...

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Contents Contents 1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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STLM75 3.4.3 3.4.4 3.4.5 3.5 READ mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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List of tables List of tables Table 1. Signal names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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STLM75 List of figures Figure 1. Logic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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Description 1 Description The STLM75 is a high-precision digital CMOS temperature sensor IC with a sigma-delta temperature-to-digital converter and an I for general applications such as personal computers, system thermal management, electronics equipment, and industrial controllers, and is packaged in ...

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STLM75 1.2 Temperature sensor output The STLM75 temperature sensor has a dedicated open drain overlimit signal/interrupt (OS/INT) output which features a thermal alarm function. This function provides a user- programmable trip and turn-off temperature. It can operate in either of ...

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Description Table 1. Signal names Pin Sym 1 SDA 2 SCL 3 OS/INT 4 GND SDA and OS/INT are open drain. Figure 2. Connections (SO8 and MSOP8/TSSOP8) 1. SDA and OS/INT ...

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STLM75 1.3 Pin descriptions See Figure 1 on page 7 to this device. 1.3.1 SDA (open drain) This is the serial data input/output pin for the 2-wire serial communication port. 1.3.2 SCL This is the serial clock input pin for ...

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Operation 2 Operation After each temperature measurement and analog-to-digital conversion, the STLM75 stores the temperature as a 16-bit two’s complement number (see selection summary on page The most significant bit (S) indicates if the temperature is positive or negative: ● ...

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STLM75 2.1 Applications information STLM75 digital temperature sensors are optimal for thermal management and thermal protection applications. They require no external components for operations except for pull- up resistors on SCL, SDA, and OS/INT outputs. A 0.1 µF bypass capacitor ...

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Operation 2.2 Thermal alarm function The STLM75 thermal alarm function provides user-programmable thermostat capability and allows the STLM75 to function as a standalone thermostat without using the serial interface. The OS output is the alarm output. This signal is an ...

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STLM75 2.4 Interrupt mode In interrupt mode, the OS output first becomes active when the measured temperature exceeds the T OS configuration register. Once activated, the OS can only be cleared by either putting the STLM75 into shutdown mode or ...

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Operation 2.5 Fault tolerance For both comparator and interrupt modes, the alarm “fault tolerance” setting plays a role in determining when the OS output will be activated. Fault tolerance refers to the number of consecutive times an error condition must ...

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STLM75 2.7 Temperature data format Table 3 shows the relationship between the output digital data and the external temperature. Temperature data for the temperature, T two’s complement word. The left-most bit in the output data stream contains temperature polarity information ...

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Functional description 3 Functional description The STLM75 registers have unique pointer designations which are defined in page 17. Whenever any READ/WRITE operation to the STLM75 register is desired, the user must “point” to the device register to be accessed. All ...

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STLM75 Table 5. Register pointers selection summary Pointer value P1 P0 Name ( TEMP Configuration CONF HYS Overtemperature 3.1.2 Configuration register The configuration register is ...

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Functional description 3.1.3 Temperature register The temperature register is a two-byte (16-bit) “Read only” register (see page 18). Digital temperatures from the T-to-D converter are stored in the temperature register in two’s complement format, and the contents of this register ...

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STLM75 3.1.5 Hysteresis temperature register (T T register is a two-byte (16-bit) READ/WRITE register that stores the user- HYS programmable lower trip-point temperature for the thermal alarm in two’s complement format (see Table 0000). The format of this register is ...

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Functional description 3.3 Serial interface Writing to and reading from the STLM75 registers is accomplished via the two-wire serial interface protocol which requires that one device on the bus initiates and controls all READ and WRITE operations. This device is ...

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STLM75 3.4.4 Data valid The state of the data line represents valid data when after a start condition, the data line is stable for the duration of the high period of the clock signal. The data on the line may ...

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Functional description 3.4.5 Acknowledge Each byte of eight bits is followed by one acknowledge bit. This acknowledge bit is a low level put on the bus by the receiver whereas the master generates an extra acknowledge related clock pulse (see ...

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STLM75 3.5 READ mode In this mode the master reads the STLM75 slave after setting the slave address (see Figure 8). Following the WRITE mode control bit (R/W=0) and the acknowledge bit, the word address 'An' is written to the ...

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Functional description Figure 9. Typical 2-byte READ from preset pointer location (e.g. temp - R/W Start Address Byte by Master Figure 10. Typical pointer set followed by an immediate READ for ...

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STLM75 3.6 WRITE mode In this mode the master transmitter transmits to the STLM75 slave receiver. Bus protocol is shown in Figure 12. Following the START condition and slave address, a logic '0' (R placed on the ...

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Functional description Figure 14 Start Address Byte by Master Most Significant Data Byte 26/40 and T WRITE HYS R/W ...

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STLM75 4 Typical operating characteristics Figure 15. Temperature variation vs. voltage 140 120 100 –20 –40 –60 2 Typical operating characteristics 3 4 Voltage (V) Doc ID 13296 Rev 12 –20 0.5 85 110 125 ...

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Maximum ratings 5 Maximum ratings Stressing the device above the ratings listed in the absolute maximum ratings table may cause permanent damage to the device. These are stress ratings only and operation of the device at these or any other ...

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STLM75 6 DC and AC parameters This section summarizes the operating measurement conditions, and the DC and AC characteristics of the device. The parameters in the DC and AC characteristics tables that follow, are derived from tests performed under the ...

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DC and AC parameters Table 12. DC and AC characteristics Sym Description V Supply voltage DD V supply current, active DD temperature conversions supply current, DD communication only Shutdown mode supply I DD1 current, serial port inactive ...

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STLM75 Figure 16. Bus timing requirements sequence SDA tBUF SCL P Table 13. AC characteristics Sym f SCL clock frequency SCL t Time the bus must be free before a new transmission can start BUF t SDA and SCL fall ...

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Package mechanical data 7 Package mechanical data In order to meet environmental requirements, ST offers these devices in different grades of ® ECOPACK packages, depending on their level of environmental compliance. ECOPACK specifications, grade definitions and product status are available ...

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STLM75 Figure 17. SO8 – 8-lead plastic small outline package mechanical drawing A2 Note: Drawing is not to scale. Table 14. SO8 – 8-lead plastic small outline package mechanical data Sym ccc ...

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Package mechanical data Figure 18. MSOP8 (TSSOP8) – 8-lead, thin shrink small outline ( mm) package mechanical drawing A ccc Note: Drawing is not to scale. Table 15. MSOP8 (TSSOP8) – 8-lead, thin shrink small outline (3 ...

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STLM75 Figure 19. Carrier tape for SO8 and MSOP8 (TSSOP8) packages T TOP COVER TAPE K 0 Table 16. Carrier tape dimensions for SO8 and MSOP8 (TSSOP8) packages Package 1.50 12.00 1.75 SO8 +0.10/ ±0.30 ±0.10 –0.00 ...

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Package mechanical data Figure 20. Reel schematic D A Full radius Table 17. Reel dimensions for 12 mm carrier tape - SO8 and MSOP8 (TSSOP8) packages A Package (max) (min) 330 mm SO8 1.5 mm (13-inch) 180 mm MSOP8 1.5 ...

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STLM75 8 Part numbering Table 18. Ordering information scheme Example: Device type STLM75 Package M = SO8 DS = MSOP8 (TSSOP8) Temperature range 2 = –55 to 125 °C Shipping method ® ECOPACK package, tape & reel ® ...

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Package marking information 9 Package marking information Figure 21. Device topside marking information (SO8) 1. Traceability codes Figure 22. Device topside marking information (MSOP8/TSSOP8) 1. Traceability codes 38/40 STLM75M2 xxxxx (1) LM75 xxxx (1) Doc ID 13296 Rev 12 STLM75 ...

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STLM75 10 Revision history Table 19. Document revision history Date Revision 23-Dec-2005 24-Feb-2006 06-Mar-2006 28-Jul-2006 22-Jan-2007 01-Mar-2007 06-Jun-2007 07-Jul-2008 18-Jul-2008 09-Apr-2009 24-Mar-2010 17-Aug-2010 1 Initial release. Updated template, characteristics (Figure Table ...

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