LM77CIMM-5 NSC [National Semiconductor], LM77CIMM-5 Datasheet
LM77CIMM-5
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LM77CIMM-5 Summary of contents
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LM77 9-Bit + Sign Digital Temperature Sensor and Thermal Window Comparator with Two-Wire Interface General Description The LM77 is a digital temperature sensor and thermal win- 2 dow comparator with ™ Serial Bus interface. The window-comparator architecture ...
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... Simplified Block Diagram Connection Diagram Ordering Information Order Number LM77CIM-3 LM77CIMX-3 LM77CIM-5 LM77CIMX-5 LM77CIMM-3 LM77CIMMX-3 LM77CIMM-5 LM77CIMMX-5 Pin Description Label Pin # SDA 1 Serial Bi-Directional Data Line. Open Drain Output SCL 2 Serial Bus Clock Input T_CRIT_A 3 Critical Temperature Alarm Open Drain Output ...
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Pin Description (Continued) FIGURE 1. Typical Application 3 DS100136-3 www.national.com ...
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... ESD Susceptibility (Note 4) Human Body Model 10 mA Machine Model 6.5V Operating Ratings −65˚C to +125˚C Specified Temperature Range (Note 6) Supply Voltage Range (+V ± =+5 Vdc 10% for LM77CIM-5, LM77CIMM-5 and +V S Typical Conditions (Note −10˚C to +65˚ −25˚C to +100˚ − ...
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... Logic Electrical Characteristics DIGITAL DC CHARACTERISTICS Unless otherwise noted, these specifications apply for +V ± LM77CIMM-5 and +V =+3.3 Vdc 10% for LM77CIM-3, LM77CIMM-3. Boldface limits apply for T S other limits =+25˚C, unless otherwise noted Symbol Parameter I High Level Output Current OH V Low Level Output Voltage ...
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... Logic Electrical Characteristics SERIAL BUS DIGITAL SWITCHING CHARACTERISTICS Unless otherwise noted, these specifications apply for +V ± 10% for LM77CIM-5 and LM77CIMM-5, +V output lines = 80 pF unless otherwise specified. Boldface limits apply for T +25˚C, unless otherwise noted. The switching characteristics of the LM77 fully meet or exceed the published specifications of the I rameters are the timing relationship between SCL and SDA signal related to the LM77 ...
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Logic Electrical Characteristics FIGURE 2. Temperature-to-Digital Transfer Function (Non-linear scale for clarity) 1.0 Functional Description The LM77 temperature sensor incorporates a band-gap type temperature sensor, 10-bit ADC, and a digital comparator with user-programmable upper and lower limit values. The comparator ...
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Functional Description terrupts just after reprogramming setpoints. Typically, sys- tem Interrupt inputs are masked prior to reprogramming trip points. By doing a read just after resetting trip points, but prior to unmasking, unexpected Interrupts are prevented. Avoid programming setpoints ...
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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 LM77 is read. 1.4 TEMPERATURE DATA FORMAT ...
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Functional Description 1.8 INTERNAL REGISTER STRUCTURE There are four data registers in the LM77, selected by the Pointer register. At power-up the Pointer is set to “00”; the location for the Temperature Register. The Pointer register latches the last ...
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Functional Description 1.9 POINTER REGISTER (Selects which registers will be read from or written to P0–P2: Register Select P3–P7: Must be kept zero. 1.10 TEMPERATURE REGISTER (Read Only): D15 D14 ...
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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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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 ...
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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 LM77 is read. FIGURE 7. Temperature Response ...
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Typical Applications FIGURE 9. Remote HVAC temperature sensor communicates via 3 wires, including thermostat signals. FIGURE 10. ACPI Compatible Terminal Alarm Shutdown. By powering the LM77 from auxilary output of the power supply, a non-functioning overheated computer can be ...
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Physical Dimensions 8-Lead (0.150" Wide) Molded Small Outline Package (SOP), Order Number LM77CIM-3, LM77CIMX-3, LM77CIM-5 or LM77CIMX-5 www.national.com inches (millimeters) unless otherwise noted JEDEC Registration Number MS-012 (variation AA), NS Package Number M08A 16 ...
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... Physical Dimensions 8-Lead (0.150" Wide) Molded Mini Small Outline Package (MSOP), Order Number LM77CIMM-3, LM77CIMMX-3, LM77CIMM-5 or LM77CIMMX-5 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 ...