LM74-3EVAL National Semiconductor, LM74-3EVAL Datasheet
LM74-3EVAL
Specifications of LM74-3EVAL
LM74-3EVAL Summary of contents
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... General Description The LM74 is a temperature sensor, Delta-Sigma analog-to- digital converter with an SPI and MICROWIRE compatible interface. The host can query the LM74 at any time to read temperature. A shutdown mode decreases power consump- tion to less than 10 µA. This mode is useful in systems where low average power consumption is critical ...
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... Marking LM74CIM-3 LM74CIM-3 LM74CIMX-3 LM74CIM-3 LM74CIM-5 LM74CIM-5 LM74CIMX-5 LM74CIM-5 LM74CIBP-3 T8 LM74CIBPX-3 T8 LM74CIBP-5 T9 LM74CIBPX-5 T9 LM74CITP-3 T10 LM74CITPX-3 T10 LM74CITP-5 T11 LM74CITPX-5 T11 www.national.com 10090902 Note: - Pin numbers are referenced to the package marking text orientation. Pin 1 is designated by the square. - Reference JEDEC Registration MO-211, variation BC - The top 4 characters designate the date code ...
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... Function FIGURE 1. COP Microcontroller Interface 3 Typical Connection From and to Controller From Controller No Connection Ground No Connection No Connection From Controller DC Voltage from 3.0V to 5.5V for the LM74CIM and 2.65V to 5.5V for the LM74CIBP and LM74CITP. Bypass with a 0.1 µF ceramic capacitor. 10090903 www.national.com ...
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... LM74CIM,LM74CIBP, and LM74CITP all other pins Machine Model Temperature-to-Digital Converter Characteristics Unless otherwise noted, these specifications apply for V + 3.6V for the LM74CIM -3 and V = 4.5V to 5.5V for the LM74 -5 (Note 6). Boldface limits apply for T all other limits =+25˚C, unless otherwise noted Parameter ...
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... SC (Clock) Low to Data Out (SO) Delay High to Data Out (SO) TRI-STATE (Clock) High to Data In (SI) Hold Time 6 t Data In (SI) Set-Up Time to SC (Clock) High 7 (Continued 4.5V to 5.5V for the LM74 -5 (Note 6). Boldface ; all other limits =+25˚C, unless otherwise noted. MAX A J Conditions −400 µA ...
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... For the LM74CIBP-3 and LM74CITP-3 (micro SMD) parts all accuracies are guaranteed over the supply range of 2.65V to 3.6V, except for the temperature ranges of -55˚C to 125˚C and −55˚C to +150˚C where the accuracy applies for the nominal supply voltage of 3.3V. For the LM74CIBP-5 and LM74CITP-5 (micro SMD) parts all accuracies are guranteed over the supply range of 4.75V to 5.25V, except for the temperature ranges of -55˚ ...
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... Note 8: Limits are guaranteed to National’s AOQL (Average Outgoing Quality Level). Note 9: This specification is provided only to indicate how often temperature data is updated. The LM74 can be read at any time without regard to conversion state (and will yield last conversion result). A conversion in progress will not be interrupted. The output shift register will be updated at the completion of the read and a new conversion restarted. Note 10: For best accuracy, minimize output loading. Higher sink currents can affect sensor accuracy with internal heating. This can cause an error of 0.64˚ ...
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... SERIAL BUS INTERFACE The LM74 operates as a slave and is compatible with SPI or MICROWIRE bus specifications. Data is clocked out on the falling edge of the serial clock (SC), while data is clocked in on the rising edge of SC. A complete transmit/receive com- ...
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... SI/O line will go into TRI-STATE. CS can be taken high at any time during the transmit phase brought low in the middle of a conversion the LM74 will complete the conversion and the output shift register will be updated after CS is brought back high. ...
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... D0–D15 set hex sets Continuous conversion mode. Note: setting D0-D15 to any other values may place the LM74 into a manufacturer’s test mode, upon which the LM74 will stop responding as described. These test modes are to be used for National Semiconductor production testing only. See Section 1.2 Serial Bus Interface for a complete discussion ...
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Serial Bus Timing Diagrams a) Reading Continuous Conversion - Single Eight-Bit Frame b) Reading Continuous Conversion - Two Eight-Bit Frames 10090914 c) Writing Shutdown Control FIGURE 7. Timing Diagrams 11 10090915 10090918 www.national.com ...
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... For the LM74, the best thermal path between the die and the outside world is through the LM74’s pins. In the SO-8 package all the pins on the LM74 will have an equal effect on the die temperature. Because the pins represent a good thermal path to the LM74 die, the LM74 will provide an accurate measurement of the temperature of the printed circuit board on which it is mounted ...
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... Typical Applications FIGURE 9. LM74 digital input control using micro-controller’s general purpose I/O. (Continued) 13 10090919 www.national.com ...
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... Physical Dimensions Order Number LM74CIM-3, LM74CIMX-3, LM74CIM-5 or LM74CIMX-5 Order Number LM74CIBP-3,LM74CIBPX-3, LM74CIBP-5, LM74CIBPX-5 The following dimensions apply to the BPD05MPB package shown above: X1=1565µm www.national.com inches (millimeters) unless otherwise noted 8-Lead Molded Small Outline Package NS Package Number M08A 5-Bump micro SMD Ball Grid Array Thick Package NS Package Number BPD05MPB ± ...
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... Physical Dimensions inches (millimeters) unless otherwise noted (Continued) 5-Bump micro SMD Ball Grid Array Thin Package Order Number LM74CITP-3,LM74CITPX-3, LM74CITP-5, LM74CITPX-5 The following dimensions apply to the TPD05QSA package shown above: X1=1590µm National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications ...