LM82_04 NSC [National Semiconductor], LM82_04 Datasheet
LM82_04
Related parts for LM82_04
LM82_04 Summary of contents
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LM82 Remote Diode and Local Digital Temperature Sensor with Two-Wire Interface General Description The LM82 is a digital temperature sensor with a 2 wire serial interface that senses the voltage and thus the temperature of a remote diode using a ...
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Connection Diagram Ordering Information Typical Application www.national.com QSOP-16 TOP VIEW Order NS Package Transport Number Number Media MQA16A 95 Units in LM82CIMQA (QSOP-16) Rail MQA16A 2500 Units on LM82CIMQAX (QSOP-16) Tape and Reel 2 10129702 10129703 ...
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Pin Descriptions Label Pin # D− 4 ADD0–ADD1 10, 6 GND 13, 15 INT 11 SMBData 12 SMBCLK 14 T_CRIT_A 16 Function floating, unconnected Left floating. PC board ...
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Absolute Maximum Ratings Supply Voltage Voltage at SMBData, SMBCLK, T_CRIT_A & INT pins Voltage at Other Pins D− Input Current Input Current at All Other Pins (Note 2) Package Input Current (Note 2) SMBData, T_CRIT_A, INT Output Sink Current Storage ...
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Logic Electrical Characteristics DIGITAL DC CHARACTERISTICS Unless otherwise noted, these specifications apply for all other limits =+25˚C, unless otherwise noted. MAX A J Symbol Parameter SMBData, SMBCLK V Logical “1” Input Voltage IN(1) V ...
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Logic Electrical Characteristics SMBus DIGITAL SWITCHING CHARACTERISTICS Unless otherwise noted, these specifications apply for V pF. Boldface limits apply for characteristics of the LM82 fully meet or exceed the published specifications of the SMBus or I ...
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Logic Electrical Characteristics 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 ...
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Logic Electrical Characteristics Note 7: Limits are guaranteed to National’s AOQL (Average Outgoing Quality Level). Note 8: The Temperature Error will vary less than Note 9: Quiescent current will not increase substantially with an active SMBus. Note 10: This specification ...
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Functional Description less than or equal to it’s corresponding HIGH setpoint, as shown in Figure 4. Figure 5 shows a simplified logic diagram for the INT output and related circuitry. * Note: Status Register Bits are reset by a ...
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Functional Description 1.4 POWER ON RESET DEFAULT STATES LM82 always powers up to these known default states: 1. Command Register set to 00h 2. Local Temperature set to 0˚C 3. Remote Temperature set to 0˚C until the LM82 senses ...
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Functional Description 1.9 COMMUNICATING with the LM82 There are 13 data registers in the LM82, selected by the Command Register. At power-up the Command Register is set to “00”, the location for the Read Local Temperature Register. The Command ...
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LM82 Registers 2.1 COMMAND REGISTER Selects which registers will be read from or written to. Data for this register should be transmitted during the Command Byte of the SMBus write communication. P7 P0-P7: Command Select Command Select Power On ...
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LM82 Registers (Continued) 2.2 LOCAL and REMOTE TEMPERATURE REGISTERS (LT, and RT) (Read Only Address 00h, and 01h): D7 MSB D7–D0: Temperature Data. One LSB = 1˚C. Two’s complement format. 2.3 STATUS REGISTER (Read Only Address 02h ...
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SMBus Timing Diagrams (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 ...
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Application Hints The LM82 can be applied easily in the same way as other integrated-circuit temperature sensors and its remote diode sensing capability allows used in new ways as well. It can be soldered to a ...
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Application Hints 3. Ideally, the LM82 should be placed within 10cm of the Processor diode pins with the traces being as straight, short and identical as possible. Trace resistance of 1Ω can cause as much as 1˚C of error. ...
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Physical Dimensions 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. As used herein: 1. ...