DS1720S+ Maxim Integrated Products, DS1720S+ Datasheet
DS1720S+
Specifications of DS1720S+
Related parts for DS1720S+
DS1720S+ Summary of contents
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FEATURES Requires no external components Supply voltage range covers from 2.7V to 5.5V Measures temperatures from –55°C to +125°C in 0.5°C increments. Fahrenheit equivalent is –67°F to +257°F in 0.9°F increments Temperature is read as a 9–bit value Converts ...
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... ORDER INFORMATION ORDERING PACKAGE NUMBER MARKING DS1720S+ DS1720 (see note) DS1720S+T&R DS1720 (see note) DS1720S DS1720 DS1720S/T&R DS1720 Note: A “+” symbol will also be marked on the package near the Pin 1 indicator. OPERATION–MEASURING TEMPERATURE A block diagram of the DS1720 is shown in Figure 1. The DS1720 measures temperatures through the use of an on– ...
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DS1720 FUNCTIONAL BLOCK DIAGRAM Figure DS1720 ...
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TEMPERATURE MEASURING CIRCUITRY Figure 2 This calculation is done inside the DS1720 to provide 0.5°C resolution. The temperature reading is provided in a 9–bit, two’s complement reading by issuing a READ TEMPERATURE command. Table 1 describes the exact relationship of ...
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Higher resolutions may be obtained by reading the temperature, and truncating the 0.5°C bit (the LSB) from the read value. This value is TEMP_READ. The value left in the counter may then be read by issuing a READ COUNTER command. ...
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THERMOSTAT OUTPUT OPERATION Figure 3 OPERATION AND CONTROL The DS1720 must have temperature settings resident in the T A configuration/status register is also used to determine the method of operation that the DS1720 will use in a particular application, as ...
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For typical thermostat operation, the DS1720 will operate in continuous mode. However, for applications where only one reading is needed at certain times, and to conserve power, the one–shot mode may be used. Note that the thermostat outputs (T last ...
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Read T [A1h] H This command reads the value of the T the next nine clock cycles clock out the 9–bit temperature limit which sets the threshold for operation of the T output. HIGH Read T [A2h] L This command ...
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DS1720 COMMAND SET Table 3 INSTRUCTION DESCRIPTION TEMPERATURE CONVERSION COMMANDS Read Temperature Temperature Reads last converted temperature value from temperature register Read Counter Reads value of count remaining from counter Read Slope Reads value of the slope accumulator Start Convert ...
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FUNCTION EXAMPLE Example: CPU sets up DS1720 for continuous conversion and thermostatic function. DS1720 MODE CPU MODE (3-WIRE ...
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READ DATA TRANSFER Figure 4 WRITE DATA TRANSFER Figure DS1720 ...
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ABSOLUTE MAXIMUM RATINGS* Voltage on Any Pin Relative to Ground Operating Temperature Storage Temperature Soldering Temperature *This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operation ...
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AC ELECTRICAL CHARACTERISTICS PARAMETER SYMBOL Temperature Conversion Time Data to CLK Setup CLK to Data Hold CLK to Data Delay CLK Low Time CLK High Time CLK Frequency CLK Rise and Fall to CLK Setup RST CLK to Hold RST ...
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DS1720 TYPICAL THERMOMETER ERROR DS1720 DS1720 ...