STCN75DS2E STMICROELECTRONICS [STMicroelectronics], STCN75DS2E Datasheet
STCN75DS2E
Related parts for STCN75DS2E
STCN75DS2E 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 C/SMBus-compatible ...
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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 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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Temperature sensor output The STCN75 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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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) S 1.3 Pin descriptions See Figure 1 on ...
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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 be ...
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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 page 17). The most significant bit (S) indicates if the temperature is positive or negative: ...
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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 0.1µF bypass capacitor on V ...
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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 the ...
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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/INT 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 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 these ...
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Table 5. Register pointers selection summary Pointer P1 P0 Name Description value ( 3.1.2 Configuration register The Configuration register is used to store the device settings such as ...
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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 the ...
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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 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 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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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 Control ...
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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 2-byte register ...
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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 bus ...
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Figure 13. T and Start by Master 24/35 WRITE HYS R Address Byte Pointer Byte ACK ...
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Typical operating characteristics Figure 14. Temperature variation vs. voltage 140 120 100 –20 –40 – Voltage (V) –20 0.5 85 110 125 5 6 AI12258 25/35 ...
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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 supply I current, serial port DD1 inactive Accuracy for corresponding range ...
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Figure 15. 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 16. SO8 – 8-pin, plastic small package outline Drawing is not to scale. Table 14. SO8 – 8-pin, plastic small outline, package mechanical data millimetres Symbol Typ Min A A1 0.10 ...
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Figure 17. MSOP8 (TSSOP8) – 8-lead, thin shrink small package (3x3) outline A ccc 1. Drawing is not to scale. Table 15. MSOP8 (TSSOP8) – 8-lead, thin shrink small package (3x3) mech. data Sym Typ 0.85 b ...
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Part numbering Table 16. Ordering information scheme Example: Device type STCN75 Package M = SO8N DS = MSOP8 (TSSOP8) Temperature range 2 = –55 to 125°C Shipping method F = ECOPACK package, Tape & Reel E = ECOPACK package, ...
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Revision history Table 17. Revision history Date Revision 25-Jul-2006 17-Nov-2006 22-Jan-2007 02-Mar-2007 06-Jun-2007 34/35 1 Initial release Changed document to new template; document status updated from target specification to preliminary data; updated footnotes in Table 1: Signal 2 V ...
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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 ...