LM90CIMM National Semiconductor, LM90CIMM Datasheet
LM90CIMM
Specifications of LM90CIMM
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LM90CIMM Summary of contents
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... LM90 Simplified Block Diagram Pentium ™ trademark of Intel Corporation. © 2002 National Semiconductor Corporation n On-board local temperature sensing n 10 bit plus sign remote diode temperature data format, 0.125 ˚C resolution n Diode fault detection circuitry n T_CRIT_A output useful for system shutdown (open diode does not activate T_CRIT_A) n ALERT output supports SMBus 2 ...
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... Connection Diagram Ordering Information LM90CIMM LM90CIMMX Pin Descriptions Label Pin # D− 3 T_CRIT_A 4 GND 5 ALERT 6 SMBData 7 SMBCLK 8 www.national.com MSOP-8 20033702 TOP VIEW Package NS Package Marking Number T11C MUA08A (MSOP-8) T11C MUA08A (MSOP-8) Function Positive Supply Voltage DC Voltage from 3 3.6 V Input Diode Current Source To Diode Anode ...
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Typical Application 3 20033703 www.national.com ...
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Absolute Maximum Ratings Supply Voltage Voltage at SMBData, SMBCLK, ALERT, T_CRIT_A Voltage at Other Pins D− Input Current Input Current at All Other Pins (Note 2) Package Input Current (Note 2) SMBData, ALERT, T_CRIT_A Output Sink Current Storage Temperature Soldering ...
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Temperature-to-Digital Converter Characteristics Unless otherwise noted, these specifications apply for all other limits MIN A MAX A Parameter Local and Remote T_CRIT Default Temperature Setting Logic Electrical Characteristics DIGITAL DC CHARACTERISTICS Unless ...
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SMBus DIGITAL SWITCHING CHARACTERISTICS Unless otherwise noted, these specifications apply for V pF. Boldface limits apply for The switching characteristics of the LM90 fully meet or exceed the published specifications of the SMBus version 2.0. The ...
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Note 7: Limits are guaranteed to National’s AOQL (Average Outgoing Quality Level). Note 8: Local temperature accuracy does not include the effects of self-heating. The rise in temperature due to self-heating is the product of the internal power dissipation of ...
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Functional Description use, once the condition that triggered the ALERT to go low is no longer present, the ALERT is de-asserted ( Figure 3 ). For example, if the ALERT output was activated by the compari- > son of ...
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Functional Description 2. Master sends a START followed by the Alert Response Address (ARA) with a Read Command. 3. Alerting Device(s) send ACK. 4. Alerting Device(s) send their Address. While transmitting their address, alerting devices sense whether their ad- ...
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Functional Description Temperature Digital Output Binary +25˚C 0001 1001 0000 0000 +1˚C 0000 0001 0000 0000 +0.125˚C 0000 0000 0010 0000 0˚C 0000 0000 0000 0000 −0.125˚C 1111 1111 1110 0000 −1˚C 1111 1111 0000 0000 −25˚C 1110 0111 ...
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Functional Description (a) Serial Bus Write to the internal Command Register followed by a the Data Byte (b) Serial Bus Write to the Internal Command Register (c) Serial Bus Read from a Register with the Internal Command Register preset ...
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Functional Description a)Step Response FIGURE 9. Digital Filter Response in a Pentium 4 processor System. The filter on and off curves were purposely www.national.com Level 2 sets maximum filtering. ...
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Functional Description 1.12 Fault Queue In order to suppress erroneous ALERT or T_CRIT triggering the LM90 incorporates a Fault Queue. The Fault Queue acts to insure a remote temperature measurement is genuinely beyond a HIGH, LOW or T_CRIT setpoint ...
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LM90 REGISTERS Command Select Address Read Address Write Address < > < > P7:P0 hex P7:P0 hex 13h 13h 14h 14h 19h 19h 20h 20h 21h 21h B0h-BEh B0h-BEh BFh BFh FEh NA FFh NA 2.2 LOCAL and REMOTE ...
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LM90 REGISTERS D7: ALERT mask: When set to “1” ALERT interrupts are masked. D6: RUN/STOP: When set to “1” SHUTDOWN is enabled. D5: is not defined and defaults to “0”. D4: Remote T_CRIT mask: When set to “1” a ...
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LM90 REGISTERS For RTOHB: Remote Temperature Offset High Byte. Power up default is LHIGH = RHIGH = 0˚C. 1LSB = 1˚C. Two’s complement format. (Read/Write Address 12h): BIT Value For RTOLB: Remote Temperature Offset High Byte. Power up default ...
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... Compensating for Diode Non-Ideality In order to compensate for the errors introduced by non-ideality, the temperature sensor is calibrated for a par- ticular processor. National Semiconductor temperature sen- sors are always calibrated to the typical non-ideality of a given processor type. The LM90 is calibrated for the non-ideality of a mobile Pentium III processor, 1.008. When ...
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Application Hints Error Caused by Non-Ideality Factor FIGURE 12. Compensating for an Untargeted Non-Ideality Factor Temperature errors associated with non-ideality may be re- duced in a specific temperature range of concern through use of the offset registers (11h and ...
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Application Hints (Continued) 4.2 PCB LAYOUT for MINIMIZING NOISE FIGURE 15. Ideal Diode Trace Layout In a noisy environment, such as a processor mother board, layout considerations are very critical. Noise induced on traces running between the remote temperature ...
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... National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. inches (millimeters) JEDEC Registration Number MO-187 Order Number LM90CIMM or LM90CIMMX NS Package Number MUA08A 2. A critical component is any component of a life ...