LM76CNM-3 National Semiconductor, LM76CNM-3 Datasheet
LM76CNM-3
Specifications of LM76CNM-3
Related parts for LM76CNM-3
LM76CNM-3 Summary of contents
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... These include thermal man- agement and protection applications in personal computers, electronic test equipment, office electronics and bio-medical applications C® registered trademark of Philips Corporation. © 2010 National Semiconductor Corporation LM76 Features ■ Window comparison simplifies design of ACPI compatible temperature monitoring and control. ■ ...
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Simplified Block Diagram Connection Diagram Ordering Information Order Number Supply Voltage LM76CHM-5 LM76CHMX-5 www.national.com SO-8 LM76 See NS Package Number M08A Temperature Acurracy Range for Accuracy ±0.5°C 25°C 5.0V ±1.0°C −10°C to 45°C ±0.5°C 25°C 5.0V ±1.0°C −10°C to 45°C ...
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Pin Descriptions Label Pin # Serial Bi-Directional Data Line, Open Drain Output, CMOS SDA 1 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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... Note 14) 2 14) 10 14 (Note 1, Note −55°C to +150°C 6) −20°C to +85°C )(Note 7) +4.5V to +5.5V S (Note 7). Boldface limits apply LM76CNM-3 LM76CHM-5 Limits Limits (Note 9) (Note 9) ±1.0 ±1.0 ±0.5 500 1000 0.5 0. MIN MAX Units (Limit) Bits ° ...
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Logic Electrical Characteristics DIGITAL DC CHARACTERISTICS Unless otherwise noted, these specifications apply for +V LM76CHM-5. Boldface limits apply for T Symbol Parameter SDA and SCL Logical “1” Input V IN(1) Voltage SDA and SCL Logical “0” Input V IN(0) Voltage ...
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... Note 7: The LM76 will operate properly over the +V and specified for rated accuracy at the nominal supply voltage of 3.3V. Accuracy of the LM76CNM-3 will degrade 0.2°C for a ±1% variation in +V value. The LM76CHM-5 is tested and specified for a rated accuracy at the nominal supply voltage of 5.0V. Accuracy of the LM76CHM-5 will degrade 0.08°C for a ± ...
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Functional Description The LM76 temperature sensor incorporates a band-gap type temperature sensor, 13-bit ADC, and a digital comparator with user-programmable upper and lower limit values. The comparator activates either the INT line for temperatures out- side the T and ...
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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 ...
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SHUTDOWN MODE Shutdown mode is enabled by setting the shutdown bit in the Configuration register via the Serial Bus. Shutdown mode re- duces power supply current to 5 μA typical. T_CRIT_A is reset if previously set. Since conversions are ...
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Alternatively, the master can issue clock cycles until SDA goes high, at which time issuing a “Stop” condition will reset the LM76. FIGURE 4. Inadvertent 8-Bit Read from 16-Bit Register where D7 is Zero (“0”) www.national.com 10 ...
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POINTER REGISTER (Selects which registers will be read from or written to P0–P2: Register Select ...
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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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Typical Pointer Set Followed by Immediate Read from Configuration Register Configuration Register Write Comparison Register Write FIGURE 6. Timing Diagrams 13 10101512 10101513 10101514 www.national.com ...
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Application Hints The temperature response graph in application designed to meet ACPI requirements. In this type of application, the temperature scale is given an arbitrary val "granularity", or the window within which temperature notification events should occur. ...
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Typical Applications FIGURE 9. ACPI Compatible Terminal Alarm Shutdown. By powering the LM76 from auxiliary output of the power supply, a non-functioning overheated computer can be powered down to preserve as much of the system as possible. FIGURE 8. ...
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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 www.national.com inches (millimeters) unless otherwise noted NS Package Number M08A 16 ...
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Notes 17 www.national.com ...
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