LM77CIM-3 National Semiconductor, LM77CIM-3 Datasheet
LM77CIM-3
Specifications of LM77CIM-3
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LM77CIM-3 Summary of contents
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... HVAC applications C® registered trademark of Philips Corporation. © 2010 National Semiconductor Corporation LM77 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 LM77CIM-3; LM77CIM-3/NOPB LM77CIMX-3; LM77CIMX-3/NOPB LM77CIM-5; LM77CIM-5/NOPB LM77CIMX-5; LM77CIMX-5/NOPB LM77CIMM-3; LM77CIMM-3/NOPB LM77CIMMX-3; LM77CIMMX-3/NOPB LM77CIMM-5; LM77CIMM-5/NOPB LM77CIMMX-5 www.national.com SOP8 or MSOP 10013602 LM77 See NS Package Number M08A or MM08A Supply Voltage Package 3.3V SOP8, M08A 3.3V ...
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... Pin Descriptions 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 GND 4 Power Supply Ground INT 5 Interrupt Open Drain Output +V 8 Positive Supply Voltage Input S A0–A1 7,6 ...
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... T Default Temperature HIGH T Default Temperature C Logic Electrical Characteristics Digital DC Characteristics Unless otherwise noted, these specifications apply for +V for LM77CIM-3, LM77CIMM-3. Boldface limits apply for T noted. Symbol Parameter V SDA and SCL Logical “1” Input IN(1) Voltage V SDA and SCL Logical “0” Input ...
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... OL T_CRIT_A Output Saturation Voltage I T_CRIT_A Delay t Output Fall Time OF Serial Bus Digital Switching Characteristics Unless otherwise noted, these specifications apply for +V for LM77CIM-3 and LM77CIMM-3, CL (load capacitance) on output lines = 80 pF unless otherwise specified. Boldface limits apply for all other limits MIN ...
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... T_CRIT setpoints (e.g HIGH discussion of the function of hysteresis refer to Section 1.1, TEMPERATURE COMPARISON, and Note 14: Default values set at power up. Note 15: Timing specifications are tested at the bus input logic levels (Vin(0)=0.3xVA for a falling edge and Vin(1)=0.7xVA for a rising edge) when the SCL and SDA edge rates are similar ...
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... For example user never read the part, and temperature went below T then INT would become active. It would stay LOW that way forever if a user never read the part. However if the user read the part, the output would be reset. Even if the condition is true, it will remain reset. The temper- ...
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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 LM77 is read. 1.4 TEMPERATURE DATA FORMAT Temperature data can be read from the Temperature and Set Point registers; and written to the Set Point registers. Tem- ...
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... For instance, if the first four bits of the temperature data indicates a critical condition, the host processor could immediately take action to remedy the excessive temperature. At the end of a read, ...
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FIGURE 4. Inadvertent 8-Bit Read from 16-Bit Register where D7 is Zero (“0”) www.national.com 10 10013608 ...
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... Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 D3–D15: Temperature Data. One LSB = 0.5°C. Two's com- plement format Fault Queue INT Polarity D4: Fault Queue - When set to 1 the Fault Queue is enabled, see Section 1.7. Power up default of “0”. D5–D7: These bits are used for production testing and must be kept zero for normal operation ...
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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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... In Comparator Interrupt Mode, the LM77 simply stops issuing interrupts. 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 LM77, as the user receives notification that a lower limit is exceeded in such a way that temperature is dropping ...
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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 LM77 is read. FIGURE 7. Temperature Response Diagram for ACPI Implementation 4.0 Typical Applications www.national.com FIGURE 8. Typical Application ...
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... 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 powered down to preserve as much of the system as possible. 15 10013617 10013619 www.national.com ...
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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 8-Lead (0.150 Wide) Molded Mini Small Outline Package (MSOP), Order Number LM77CIMM-3, LM77CIMMX-3, LM77CIMM-5 or LM77CIMMX-5 www.national.com inches (millimeters) unless otherwise noted JEDEC Registration Number MS-012 (variation AA), ...
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