MAX31722 MAXIM [Maxim Integrated Products], MAX31722 Datasheet
MAX31722
Related parts for MAX31722
MAX31722 Summary of contents
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... Rev 0; 11/10 Digital Thermometers and Thermostats General Description The MAX31722/MAX31723 digital thermometers and thermostats with an SPI™/3-wire interface provide tem- perature readings that indicate the device temperature. No additional components are required; the devices are truly temperature-to-digital converters. Temperature readings are communicated from the device over an SPI interface or a 3-wire serial interface ...
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... SYMBOL Supply Voltage Input Logic-High Input Logic-Low DC ELECTRICAL CHARACTERISTICS (V = 1.7V to 3.7V -55NC to +125NC, unless otherwise noted PARAMETER SYMBOL MAX31722 Thermometer Error MAX31723 Thermometer Error Resolution Conversion Time t CONVT Logic 0 Output (SDO, TOUT) Logic 1 Output (SDO) Leakage Current Active Current Shutdown Current 2 Operating Junction Temperature Range ...
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Digital Thermometers and Thermostats AC ELECTRICAL CHARACTERISTICS: 3-WIRE INTERFACE (V = 1.7V to 3.7V -55NC to +125NC, unless otherwise noted.) (Figures PARAMETER SYMBOL Data to SCLK Setup SCLK to Data Hold SCLK to Data ...
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Digital Thermometers and Thermostats with SPI/3-Wire Interface SCLK t CDH I/O* *I/O IS SDI AND SDO CONNECTED TOGETHER. Figure 1. Timing Diagram: 3-Wire Read Data Transfer SCLK I/O* ...
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Digital Thermometers and Thermostats SCLK t CDH t DC SDI A7 SDO WRITE ADDRESS BYTE NOTE: SCLK CAN BE EITHER POLARITY, TIMING SHOWN FOR CPOL = 1. Figure 3. Timing Diagram: SPI Read Data Transfer CE t ...
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Digital Thermometers and Thermostats with SPI/3-Wire Interface (T = +25°C, unless otherwise noted.) A TEMPERATURE CONVERSION ACTIVE SUPPLY CURRENT vs. TEMPERATURE 1200 1000 V = 3.7V DD 800 600 400 V = 1.7V DD 200 0 -55 -35 -15 5 ...
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... V Supply Voltage. Power-supply input. DD Detailed Description The MAX31722/MAX31723 are factory-calibrated tem- perature sensors that require no external components. The user can alter the configuration/status register to place the device in a continuous temperature conversion mode or into a one-shot conversion mode. In the continu- ous conversion mode, the devices continuously convert the temperature and store the result in the temperature register ...
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Digital Thermometers and Thermostats with SPI/3-Wire Interface Measuring Temperature The core of the devices’ functionality is its direct-to-digital temperature sensor. The devices measure temperature through the use of an on-chip temperature measure- ment technique with a -55NC to +125NC operating ...
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Digital Thermometers and Thermostats The devices’ thermostat can be programmed to power up in either comparator mode or interrupt mode, which activate and deactivate the open-drain thermostat output (TOUT) based on user-programmable trip points (T and T ). The T ...
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Digital Thermometers and Thermostats with SPI/3-Wire Interface In either mode, once TOUT has been deactivated only reactivated when the measured temperature falls below the T value. Thus, this interrupt/clear pro- LOW cess is cyclical between T and T ...
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Digital Thermometers and Thermostats Table 3. Configuration/Status Register Bit Descriptions (continued) R1: Thermostat resolution bit 1. Factory power-up state = 0 and is stored in nonvolatile memory. Sets the con- BIT 2 version resolution (see Table 4). R0: Thermostat resolution ...
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Digital Thermometers and Thermostats with SPI/3-Wire Interface CPOL = 1 CE SCLK CPOL = 0 CE SCLK NOTE: CPOL IS A BIT THAT IS SET IN THE MICROCONTROLLER’S CONTROL REGISTER. Figure 7. Serial Clock as a Function of Microcontroller Clock ...
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Digital Thermometers and Thermostats CE SCLK SDI SDO HIGH-Z Figure 8. SPI Single-Byte Read CE SCLK SDI SDO HIGH-Z Figure 9. SPI Single-Byte Write CE SCLK WRITE SDI SDI READ SDO Figure 10. SPI ...
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Digital Thermometers and Thermostats with SPI/3-Wire Interface CE SCLK I/ *I/O IS SDI AND SDO CONNECTED TOGETHER. Figure 11. 3-Wire Single-Byte Transfer CE SCLK ADDRESS I/O* BYTE *I/O IS SDI AND SDO CONNECTED TOGETHER. Figure 12. 3-Wire ...
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Digital Thermometers and Thermostats REVISION REVISION NUMBER DATE 0 11/10 Initial release Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right ...