lm76chmx-5 National Semiconductor Corporation, lm76chmx-5 Datasheet
lm76chmx-5
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lm76chmx-5 Summary of contents
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... ® registered trademark of Philips Corporation. © 2003 National Semiconductor Corporation Features n Window comparison simplifies design of ACPI compatible temperature monitoring and control. n Serial Bus interface n Separate open-drain outputs for Interrupt and Critical Temperature shutdown ± ...
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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 ± 5.0V 0.5˚C 25˚C ± 1.0˚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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Absolute Maximum Ratings Supply Voltage Voltage at any Pin Input Current at any Pin Package Input Current (Note 2) T_CRIT_A and INT Output Sink Current T_CRIT_A and INT Output Voltage Storage Temperature Soldering Information, Lead Temperature SOP Package (Note 3) ...
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Logic Electrical Characteristics DIGITAL DC CHARACTERISTICS Unless otherwise noted, these specifications apply for for +V ± LM76CNM-3 and for +V =+5.0 Vdc S limits =+25˚C, unless otherwise noted Symbol Parameter V SDA and SCL Logical ...
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Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. DC and AC electrical specifications do not apply when operating the device beyond its rated operating conditions. Note 2: When the input voltage (V ) ...
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Functional Description 1.1.2 Hardwire Outputs The T_CRIT_A hardwire output mirrors the T_CRIT_A flag, when the flag is true, the T_CRIT_A output is asserted at all times regardless of mode. Reading the LM76 has no effect on the T_CRIT_A output, ...
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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 ...
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Functional Description and T_CRIT_A outputs. The fault queue is enabled by set- ting bit 4 of the Configuration Register high (see Section 1.11). 1.8 INTERNAL REGISTER STRUCTURE There are four data registers in the LM76, selected by the Pointer ...
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POINTER REGISTER (Selects which registers will be read from or written to): P7 P0–P2: Register Select P3–P7: Must be kept zero. (Read Only): D15 D14 D13 D12 D11 Sign MSB Bit 10 ...
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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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Application Hints The temperature response graph in Figure 7 depicts a typi- cal application designed to meet ACPI requirements. In this type of application, the temperature scale is given an arbi- trary value of "granularity", or the window within ...
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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 ...
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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 ...
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... 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. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant ...