LM92CIM National Semiconductor, LM92CIM Datasheet
LM92CIM
Specifications of LM92CIM
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LM92CIM Summary of contents
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... Separate open-drain outputs for Interrupt and Critical Temperature shutdown Simplified Block Diagram ® registered trademark of Philips Corporation. © 2005 National Semiconductor Corporation n Shutdown mode to minimize power consumption LM92s can be connected to a single bus n 12-bit + sign output n Operation up to 150˚C Key Specifications ...
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... Connection Diagram Ordering Information Order Number LM92CIM LM92CIMX 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 ...
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... Supply Voltage Range (+ Soldering process must comply with National Semiconduc- tor’s Reflow Temperature Profile specifications. Refer to 6.5V www.national.com/packaging. (Note 3) −65˚C to +125˚C = +2.7V to +5.5V for LM92CIM . Boldface limits apply for +25˚C, unless otherwise noted. J Conditions T = +30˚ 3.3V to 4.0V ...
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... J Conditions 4.0 mA OUT (Note 14 400 +2.7V to +5.5V for LM92CIM . Boldface limits apply for +25 ˚C, unless otherwise noted. CL (load capacitance) on output lines = 80 pF unless all other limits MIN MAX Conditions 4 Typical Limits (Note 7) (Note 8) (Limit 0.7 V (min +0.3 V (max) S − ...
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... JA Note 6: While the LM92 has a full-scale-range in excess of 128 ˚C, prolonged operation at temperatures above 125 ˚C is not recommended. Note 7: Typicals are ˚C and represent most likely parametric norm. ...
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... A Limits at intermediate temperatures can be calculated using a straight line interpolation as shown in the following graphs: Note 10: 12 bits + sign, two’s complement Note 11: Linearity Error is defined as the worse case difference of an actual reading to that of a calculated reading derived from the straight line whose endpoints are measured at 30˚ ...
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... Note 13: This specification is provided only to indicate how often temperature data is updated. The LM92 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. Note 14: For best accuracy, minimize output loading. 10k pull-ups resistors should be sufficient. Higher sink currents can affect sensor accuracy with internal heating. This can cause an error of 0.64 ˚ ...
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... An “event” for Event Interrupt Mode is defined as: 1. Transitioning upward across a setpoint Transitioning downward across a setpoint’s correspond- ing hysteresis (after having exceeded that setpoint). For example user never read the part, and temperature went below T then INT would become active. It would LOW stay that way forever if a user never read the part ...
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... Comparator Interrupt Mode is drawn as if the user never reads the part. If the user does read, the outputs will go high once read instruction is executed and, if the fault condition still exists, go low at the end of the next conversion. 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- perature data can be read at any time, although reading faster than the conversion time of the LM92 will prevent data from being updated ...
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... The first data byte is the most significant byte with most significant bit first, permitting only as much data as neces- sary to be read to determine the temperature condition. For instance, if the first four bits of the temperature data indi- cates a critical condition, the host processor could immedi- ately take action to remedy the excessive temperature. At ...
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... D12 D11 Sign MSB Bit 10 Bit 9 Bit 8 D0–D2: Status Bits D3–D15: Temperature Data. One LSB = 0.0625˚C. Two’s complement format. 1.11 CONFIGURATION REGISTER (Read/Write D0: Shutdown - When set to 1 the LM92 goes to low power shutdown mode. Power up default of “0”. ...
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... Functional Description D3–D15 T_CRIT Trip Temperature Data. Power up default is T HYST LOW HIGH T = 2˚C. HYST T is subtracted from T , and T_CRIT, and added to T HYST HIGH Avoid programming setpoints so close that their hysteresis values overlap. See Section 1.1. 1.13 Manufacturer’s Identification Register ...
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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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... Interrupt Mode, the LM92 simply stops issuing inter- rupts. 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 LM92, 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 LM92 is read. FIGURE 7. Temperature Response Diagram for ACPI Implementation 4.0 Typical Applications FIGURE 8. Typical Application ...
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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 LM92 from auxilary output of the power supply, a non-functioning overheated computer can be powered down to preserve as much of the system as www.national.com (Continued) possible ...
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... Deutsch Tel: +49 (0) 69 9508 6208 English www.national.com Français Tel: +33 ( 8790 Order Number LM92CIM or LM92CIMX NS Package Number M08A 2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system affect its safety or effectiveness ...