STLM75 STMicroelectronics, STLM75 Datasheet

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... Shutdown mode to minimize power consumption ■ Output pin (open drain) can be configured for interrupt or comparator/thermostat mode (Dual Purpose Event Pin) ■ Packages: – SO8 (a) – MSOP8 (TSSOP8) a. Contact locat ST sales office for availability June 2007 SO8 (M) MSOP8 (TSSOP8) (DS) Rev 7 STLM75 1/37 www.st.com 1 ...

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Contents 1 Summary description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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Data valid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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... Configuration register format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Table 7. Temperature register format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Table 8. T and T register format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 OS HYS Table 9. STLM75 serial bus slave addresses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Table 10. Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Table 11. Operating and AC measurement conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Table 12. DC and AC characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Table 13. AC characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Table 14. SO8 – 8-lead plastic small outline package mechanical data Table 15. MSOP8 (TSSOP8) – ...

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List of figures Figure 1. Logic Diagram ...

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... Three pins (A0, A1, and A2) are available for address selection, and enable the user to connect devices on the same bus without address conflict. In addition, the serial interface gives the user easy access to all STLM75 registers to customize operation of the device. 6/37 ...

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... Comparator mode, and ● Interrupt mode. At power-up the STLM75 immediately begins measuring the temperature and converting the temperature to a digital value. The measured temperature value is compared with a temperature limit (which is stored in the 16-bit (T ) READ/WRITE register), and the hysteresis temperature (which is stored in ...

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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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... STLM75 is used in a noisy environment (see The active state of the OS output can be changed via the Polarity Bit (POL) in the Configuration register. The power-up default is active-low. If the user does not wish to use the thermostat capabilities of the STLM75, the OS output should be left floating. Note: If the thermostat is not used, the T system data ...

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... 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 recommended. The sensing device of STLM75 is the chip itself. The typical interface connection for this type of digital sensor is shown in Intended Applications include: ● ...

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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 drain output, and at power-up, this pin is configured with active-low polarity by default. ...

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... OS/INT pin occur only when the STLM75 is read or placed into Shutdown mode. Otherwise, OS/INT would remain active independently for any event. Figure 5. OS output temperature response diagram 1. These interrupt mode resets of O.S. occur only when STLM75 is read or placed in shutdown. Otherwise, O.S. would remain active indefinitely for any event.. HYS Figure 5 illustrates typical OS output temperature response ...

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... Bit in the Configuration register controls Shutdown mode. When SD is changed to logic '1,' the conversion in progress will be completed and the result stored in the Temperature register, after which the STLM75 will go into a low-power standby state. The OS output will be cleared if the thermostat is operating in Interrupt mode and the OS will remain unchanged in Comparator mode ...

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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 user-accessible registers can be accessed via the digital serial interface at ...

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... Table 6. Configuration register format MSB Byte Bit7 STLM75 Reserved Default 0 Keys Shutdown Control Bit M = Thermostat Mode POL = Output Polarity FT0 = Fault Tolerance0 Bit 1. Indicates Operation mode Comparator mode, and 1 = Interrupt mode (see Interrupt mode on page 2 ...

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... Temperature register if a read cycle is not ongoing. The STLM75 is continuously evaluating fault conditions regardless of READ or WRITE activity on the bus READ is ongoing, the previous temperature will be read. The readable temperature will be updated upon the completion of the next T-to-D conversion that is not masked by a read cycle ...

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... TLSB = Temperature LSB TD = Temperature Data Note: These are comparable formats to the DS75 and LM75. 3.2 Power-up default conditions The STLM75 always powers up in the following default states: ● Thermostat mode = Comparator Mode ● Polarity = Active-low ● Fault tolerance = 1 fault (i.e., relevant bits set to '0' in the Configuration register) ● ...

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... WRITE operations. This device is called the “master” device. The master device also generates the SCL signal which provides the clock signal for all other devices on the bus. These other devices on the bus are called “slave” devices. The STLM75 is a slave device (see Table 9) ...

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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 address pointer. There are two READ modes: ● ...

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... Most Significant Data Byte ACK ACK by by STLM75 Master Data Byte ACK No ACK by by STLM75 Master , HYS Stop Least Significant Data Byte Cond. No ACK by by Master Master ...

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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 and indicates to the addressed device that word address will follow and written to the on-chip address pointer. ...

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... Master Most Significant Data Byte 26/37 WRITE HYS Pointer Byte ACK ACK by STLM75 STLM75 Least Significant Data Byte ACK by STLM75 STLM75 Stop Cond. ACK by by Master AI12232 ...

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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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... These are stress ratings only and operation of the device at these or any other conditions above those indicated in the Operating sections of this specification is not implied. Exposure to Absolute maximum rating conditions for extended periods may affect device reliability. Refer also to the STMicroelectronics SURE Program and other relevant quality documents. Table 10. ...

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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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... Transmitter must internally provide a hold time to bridge the undefined region (300ns max) of the falling edge of SCL. 3. For SMBus compatibility, the STLM75 supports bus time-out. Holding the SDA line low for a time greater than time-out will cause the STLM75 to reset the SDA to the idle state of serial bus communication (SDA set to high). tF ...

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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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... DS = MSSOP8 (TSSOP8) Temperature Range 2 = –55 to 125°C Shipping Method F = ECOPACK Package, Tape & Reel E=ECOPACK Package, Tube 1. Contact local ST sales office for availability For other options, or for more information on any aspect of this device, please contact the ST Sales Office nearest you. (1) STLM75 35/37 ...

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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 time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale. ...