STCN75M2E STMicroelectronics, STCN75M2E 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 ± ° +100 C ° ■ ...

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

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STCN75 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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STCN75 List of figures Figure 1. Logic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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Description 1 Description The STCN75 is a high-precision digital CMOS temperature sensor IC with a sigma-delta temperature-to-digital converter and page 7 targeted for general applications such as personal computers, system thermal management, electronics equipment, and ...

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STCN75 1.2 Temperature sensor output The STCN75 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 Figure 2. Connections (SO8 and TSSOP8) 1. SDA and OS/INT are open drain. Figure 3. Functional block diagram Temperature Sensor and Analog-to-Digital Converter (ADC 1.3 Pin descriptions See Figure 1 on ...

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STCN75 1.3.4 GND Ground the reference for the power supply. It must be connected to system ground. 1.3.5 A2, A1, A0 A2, A1, and A0 are selectable address pins for the 3 LSBs of the I They can ...

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Operation 2 Operation After each temperature measurement and analog-to-digital conversion, the STCN75 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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STCN75 2.1 Applications information STCN75 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 2.3 Comparator mode In comparator mode, each time a temperature-to-digital (T-to-D) conversion occurs, the new digital temperature is compared to the value stored in the T tolerance number of consecutive temperature measurements are greater than the value stored in ...

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STCN75 2.5 Fault tolerance For both comparator and interrupt modes, the alarm “fault tolerance” setting plays a role in determining when the OS/INT output will be activated. Fault tolerance refers to the number of consecutive times an error condition must ...

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Operation 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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STCN75 3 Functional description The STCN75 registers have unique pointer designations which are defined in page 16. Whenever any READ/WRITE operation to the STCN75 register is desired, the user must “point” to the device register to be accessed. All of ...

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Functional description Table 5. Register pointers selection summary Pointer P1 P0 Name value (H) Temperature TEMP register Configuration CONF register Hysteresis register HYS Overtemperature shutdown ...

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STCN75 3.1.3 Temperature register The temperature register is a two-byte (16-bit) “Read only” register (see temperatures from the T-to-D converter are stored in the temperature register in two’s complement format, and the contents of this register are updated each time ...

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Functional description 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 (i.e., 0100 1011 0000 0000). The ...

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STCN75 3.3 Serial interface Writing to and reading from the STCN75 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 called ...

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Functional description 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 ...

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STCN75 Figure 6. Acknowledgement sequence SCL FROM MASTER DATA OUTPUT BY TRANSMITTER DATA OUTPUT BY RECEIVER 3.5 READ mode In this mode the master reads the STCN75 slave after setting the slave address (see Figure 7). Following the WRITE mode ...

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Functional description Figure 8. Typical 2-byte READ from preset pointer location (e.g. temp - R/W Start Address Byte by Master Figure 9. Typical pointer set followed by an immediate READ for ...

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STCN75 3.6 WRITE mode In this mode the master transmitter transmits to the STCN75 slave receiver. Bus protocol is shown in Figure 11. Following the START condition and slave address, a logic '0' (R placed on the ...

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Functional description Figure 13 Start by Master 24/37 and T WRITE HYS R/W 0 Address Byte ACK by STCN75 ...

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STCN75 4 Typical operating characteristics Figure 14. Temperature variation vs. voltage 140 120 100 –20 –40 –60 2 Typical operating characteristics 3 4 Voltage (V) Doc ID 13307 Rev 8 –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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STCN75 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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STCN75 Figure 15. Bus timing requirements sequence SDA t BUF SCL P Table 13. AC characteristics Sym f SCL clock frequency SCL Time the bus must be free before a new transmission can start t BUF t SDA and SCL ...

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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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STCN75 Figure 16. SO8 – 8-lead, plastic small outline (4. 3.90 mm) package mechanical drawing A2 1. Drawing is not to scale. Table 14. SO8 – 8-lead, plastic small outline (4. 3.90 mm) package mechanical data ...

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Package mechanical data Figure 17. MSOP8 (TSSOP8) – 8-lead, thin shrink small outline ( mm) package mechanical drawing A ccc 1. Drawing is not to scale. Table 15. MSOP8 (TSSOP8) – 8-lead, thin shrink small outline (3 ...

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STCN75 Figure 18. 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 19. Reel schematic D A Full radius Table 17. Reel dimensions for 12 mm carrier tape - SO8 and MSOP8 (TSSOP8) packages A B (max) (min) 330 mm 1.5 mm (13 inch) 34/37 40mm min. Access ...

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STCN75 8 Part numbering Table 18. Ordering information scheme Example: Device type STCN75 Package M = SO8 DS = MSOP8 (TSSOP8) Temperature range 2 = –55 to 125 °C Shipping method ® ECOPACK package, tape & reel ® ...

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Revision history 9 Revision history Table 19. Revision history Date 25-Jul-2006 17-Nov-2006 22-Jan-2007 02-Mar-2007 06-Jun-2007 17-Jul-2008 09-Apr-2009 10-May-2010 36/37 Revision 1 Initial release Changed document to new template; document status updated from target specification to preliminary data; updated footnotes in ...

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... STCN75 Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale. ...