LM76-NEVAL National Semiconductor, LM76-NEVAL Datasheet
LM76-NEVAL
Specifications of LM76-NEVAL
Related parts for LM76-NEVAL
LM76-NEVAL Summary of contents
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... Serial Bus interface n Separate open-drain outputs for Interrupt and Critical Temperature shutdown ± 0.5˚C at 25˚C. The n Shutdown mode to minimize power consumption LM76s can be connected to a single bus n 12-bit + sign output; full-scale reading of over 127˚C Key Specifications j Supply Voltage j ...
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... Simplified Block Diagram Connection Diagram Ordering Information Order Number Supply Voltage LM76CHM-5 LM76CHMX-5 LM76CNM-3 LM76CNMX-3 www.national.com SO-8 10101502 LM76 See NS Package Number M08A Temperature Acurracy Range for Accuracy ± 5.0V 0.5˚C 25˚C ± 1.0˚C −10˚C to 45˚C ± ...
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Pin Description Label Pin # SDA 1 Serial Bi-Directional Data Line, Open Drain Output, CMOS Logic Level SCL 2 Serial Bus Clock Input, CMOS Logic Level T_CRIT_A 3 Critical Temperature Alarm, Open Drain Output GND 4 Power Supply Ground INT ...
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... T_CRIT_A and INT Output Voltage Storage Temperature Soldering Information, Lead Temperature SOP Package (Note 3) Temperature-to-Digital Converter Characteristics Unless otherwise noted, these specifications apply for +V for the LM76CHM-5. (Note 7). Boldface limits apply for T wise noted. Parameter Accuracy (Note −25˚C to +125˚C for A LM76CNM +70˚ ...
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... Boldface limits apply for T wise noted. The switching characteristics of the LM76 fully meet or exceed the published specifications of the I lowing parameters are the timing relationship between SCL and SDA signal related to the LM76. They are not the I specifications. Symbol ...
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... Note 10: 12 bits + sign, two’s complement Note 11: This specification is provided only to indicate how often temperature data is updated. The LM76 can be read at any time without regard to conversion state (and will yield last conversion result conversion is in process it will be interrupted and restarted after the end of the read. ...
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... Average Power on Reset Voltage 1.3 SERIAL BUS INTERFACE to set the output The LM76 operates as a slave on the Serial Bus, so the SCL line is an input (no clock is generated by the LM76) and the SDA line is a bi-directional serial data line. According to Serial Bus specifications, the LM76 has a 7-bit slave ad- dress. The five most significant bits of the slave address are hard wired inside the LM76 and are “ ...
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... Functional Description Note: Event Interrupt mode is drawn as if the user is reading the part. If the user doesn’t read, the outputs would go low and stay that way until the LM76 is read. 1.4 TEMPERATURE DATA FORMAT Temperature data can be read from the Temperature and Set Point registers ...
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... HIGH read its last byte). An inadvertent 8-bit read from a 16-bit register, with the D7 bit low, can cause the LM76 to stop in a state where the SDA line is held low as shown in Figure 4. This can prevent any further bus communication until at least 9 additional clock cycles have occurred ...
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... D0: Shutdown - When set to 1 the LM76 goes to low power shutdown mode. Power up default of “0”. D1: Interrupt mode - 0 is Comparator Interrupt mode Event Interrupt mode. Power up default of “0”. D2, D3: T_CRIT_A and INT Polarity - 0 is active low active high. Outputs are open-drain. Power up default of “0” ...
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I C Timing Diagrams Typical 2-Byte Read From Preset Pointer Location Such as Temp or Comparison Registers Typical Pointer Set Followed by Immediate Read for 2-Byte Register such as Temp or Comparison Registers Typical 1-Byte Read from Configuration ...
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I C Timing Diagrams Typical Pointer Set Followed by Immediate Read from Configuration Register www.national.com (Continued) Configuration Register Write Comparison Register Write FIGURE 6. Timing Diagrams 12 10101512 10101513 10101514 ...
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... The 2nd event is another identical rise in temperature. The 3rd event is typical of a drop in temperature. This is one of the conditions that demonstrates the power of the LM76, as the user receives notification that a lower limit is exceeded in such a way that temperature is dropping. The Critical Alarm Event activates the separate T_CRIT_A output ...
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... Application Hints Note: Event Interrupt mode is drawn as if the user is reading the part. If the user doesn’t read, the outputs would go low and stay that way until the LM76 is read. FIGURE 7. Temperature Response Diagram for ACPI Implementation 4.0 Typical Applications www ...
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... Typical Applications FIGURE 9. ACPI Compatible Terminal Alarm Shutdown. By powering the LM76 from auxilary output of the power supply, a non-functioning overheated computer can be powered down to preserve as much of the system as (Continued) possible. 15 10101519 www.national.com ...
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... Physical Dimensions 8-Lead (0.150" Wide) Molded Small Outline Package (SOP), JEDEC Order Number LM76CNM-3, LM76CNMX-3, LM76CHM-5 or LM76CHM-5X LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION ...