STLM75DS2E STMICROELECTRONICS [STMicroelectronics], STLM75DS2E Datasheet
STLM75DS2E
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STLM75DS2E Summary of contents
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Digital temperature sensor and thermal watchdog Features ■ Measures temperatures from –55°C to +125°C (–67°F to +257°F) – ±2°C accuracy from –25°C to +100°C (max) ■ Low operating current: 125µA (typ) ■ No external components required 2 ■ 2-Wire I ...
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Contents 1 Summary description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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Data valid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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List of tables Table 1. Signal names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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List of figures Figure 1. Logic Diagram ...
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Summary description The STLM75 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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Temperature sensor output The STLM75 Temperature Sensor has a dedicated open drain Over-Limit 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 two ...
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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 TSSOP8) 1. ...
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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 the ...
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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 page 18). The most significant Bit (S) indicates if the temperature is positive or negative: ...
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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 0.1µF bypass capacitor on V ...
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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 open ...
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Interrupt mode In Interrupt mode, the OS output first becomes active when the measured temperature exceeds the T value a consecutive number of times as determined by the FT value in the OS Configuration register. Once activated, the OS ...
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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 be ...
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Temperature data format Table 3 shows the relationship between the output digital data and the external temperature. Temperature data for the Temperature, T represented as a 9-bit, two’s complement word. The left-most bit in the output data stream contains ...
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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 of these ...
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Table 5. Register pointers selection summary Pointer P1 P0 Value ( 3.1.2 Configuration register The Configuration register is used to store the device settings such as Device Operation ...
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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 are updated ...
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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 8). This register defaults to 75°C at power-up ...
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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 called the ...
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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 be ...
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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 generate an ...
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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 on-chip ...
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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 2-byte register ...
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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 bus ...
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Figure 14. T and R/W Start Address Byte by Master Most Significant Data Byte 26/37 WRITE HYS ...
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Typical operating characteristics Figure 15. Temperature variation vs. voltage 140 120 100 –20 –40 – Voltage (V) –20 0.5 85 110 125 5 6 AI12258 27/37 ...
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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 conditions above ...
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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 Measurement ...
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Table 12. DC and AC characteristics Sym Description V Supply Voltage DD V Supply Current, DD Active Temperature Conversions Supply Current, DD Communication only Shutdown mode I Supply Current, serial DD1 port inactive Accuracy for corresponding range ...
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Figure 16. Bus timing requirements sequence SDA tBUF tHD:STA tR SCL P S 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 ...
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Package mechanical data In order to meet environmental requirements, ST offers these devices in ECOPACK packages. These packages have a Lead-free second level interconnect. The category of second Level Interconnect is marked on the package and on the inner ...
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Figure 17. SO8 – 8-lead plastic small package outline A2 Note: Drawing is not to scale. Table 14. SO8 – 8-lead plastic small outline package mechanical data Sym Typ ccc D 4.90 E 6.00 E1 ...
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Figure 18. MSOP8 (TSSOP8) – 8-lead, thin shrink small package (3x3) outline A ccc Note: Drawing is not to scale. Table 15. MSOP8 (TSSOP8) – 8-lead, thin shrink small package (3x3) mechanical data Sym Typ 0.85 b ...
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Part numbering Table 16. Ordering information scheme Example: Device Type STLM75 Package M = SO8 DS = MSSOP8 (TSSOP8) Temperature Range 2 = –55 to 125°C Shipping Method F = ECOPACK Package, Tape & Reel E=ECOPACK Package, Tube 1. ...
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Revision History Table 17. 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 36/37 1 Initial release. Updated template, characteristics (Figure Table 11, 12, 13) 3 Updated ...
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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 ...