LM89CIM NSC [National Semiconductor], LM89CIM Datasheet
LM89CIM
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LM89CIM Summary of contents
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LM89 ± 0.75˚C Accurate, Remote Diode and Local Digital Temperature Sensor with Two-Wire Interface General Description The LM89 is an 11-bit digital temperature sensor with a 2-wire System Management Bus (SMBus) serial interface. The LM89 accurately measures its own temperature ...
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... Connection Diagram Ordering Information Package Part Number Marking LM89CIMM LM89-1CIMM LM89CIMMX LM89-1CIMMX LM89CIM LM89CIM LM89-1CIM LM89-1CIM LM89CIMX LM89CIM LM89-1CIMX LM89-1CIM Pin Descriptions Label Pin # D− 3 T_CRIT_A 4 GND 5 ALERT 6 SMBData 7 SMBCLK 8 www.national.com MSOP-8 or SOIC-8 TOP VIEW NS Package Number T15C ...
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Typical Application 3 20041503 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 Temperature-to-Digital ...
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Temperature-to-Digital Converter Characteristics Unless otherwise noted, these specifications apply for V ≤T ≤ all other limits MIN A MAX A Parameter Remote T_CRIT Default Temperature Setting Logic Electrical Characteristics DIGITAL DC CHARACTERISTICS Unless otherwise noted, ...
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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 The LM89 temperature sensor incorporates a delta V based temperature sensor using a Local or Remote diode and a 10-bit plus sign ADC (Delta-Sigma Analog-to-Digital Converter). The LM89 is compatible with the serial SMBus version 2.0 two-wire ...
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Functional Description FIGURE 3. ALERT Comparator Temperature Response Diagram 1.2.2 ALERT Output as an Interrupt The LM89’s ALERT output can be implemented as a simple interrupt signal when it is used to trigger an interrupt service routine. In such ...
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Functional Description 1. Master Senses SMBus alert line low 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 ...
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Functional Description available in two 8-bit registers: Temperature Digital Output Binary +125˚C 0111 1101 0000 0000 +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 ...
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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 FIGURE REGISTER at BFh. The filter can be set according to the following table Step Response FIGURE 9. Digital Filter Response in a Pentium 4 processor ...
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Functional Description 1.12 FAULT QUEUE In order to suppress erroneous ALERT or T_CRIT triggering the LM89 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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LM89 Registers (Continued) Command Select Address Read Address Write Address < > < > P7:P0 hex P7:P0 hex 12h 12h 13h 13h 14h 14h 19h 19h 20h 20h 21h 21h B0h-BEh B0h-BEh BFh BFh FEh NA FFh NA 2.2 ...
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LM89 Registers (Continued) 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 diode temperature reading that exceeds T_CRIT setpoint will not activate ...
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LM89 Registers (Continued) For RTOHB: Remote Temperature Offset High Byte. Power up default is LHIGH = RHIGH = 0˚C. 1 LSB = 1˚C. Two’s complement format. (Read/Write Address 12h): BIT Value For RTOLB: Remote Temperature Offset High Byte. Power ...
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Applications Hints optimized to measure the remote thermal diode of a 0.13 micron Pentium Mobile Pentium 4 Processor-M pro- cessor. A discrete diode can also be used to sense the temperature of external objects or ambient ...
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Applications Hints 3.2 PCB LAYOUT for MINIMIZING NOISE FIGURE 11. 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 diode ...
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... Wide) Molded Narrow Small-Outline Package (SOIC), 8-Lead Molded Mini-Small-Outline Package (MSOP), JEDEC Registration Number MS-012 Order Number LM89CIM or LM89CIMX NS Package Number M08A JEDEC Registration Number MO-187 Order Number LM89CIMM or LM89CIMMX NS Package Number MUA08A 19 www.national.com ...
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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. For the most current product information ...