LM40CIMTX/NOPB National Semiconductor, LM40CIMTX/NOPB Datasheet
LM40CIMTX/NOPB
Specifications of LM40CIMTX/NOPB
Related parts for LM40CIMTX/NOPB
LM40CIMTX/NOPB Summary of contents
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... General Description The LM40 is a hardware monitor that measures 3 tempera- ture zones, 5 voltages and has a single-wire interface com- patible with National Semiconductor’s SensorPath bus. Sen- sorPath data is pulse width encoded, thereby allowing the LM40 to be easily connected to many general purpose micro-controllers ...
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Connection Diagram TSSOP-14 Top View National Package Number MTC14C Pin Description Pin Number Pin Name GND 3 V+/+3.3V_SBY 4 SWD 5 ADD 6 +1.2V 7 +2. D1-, D2 D1+, D2+ 12 +5V ...
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Block Diagram 3 20068403 www.national.com ...
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Absolute Maximum Ratings (Notes Supply Voltage (V ) Voltage at Any Digital Input or Output Pin Voltage on 12V Analog Input Voltage on 5V Analog Input Voltage on D1+ and D2+ −0 (V+ + 0.05 ...
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TEMPERATURE-TO-DIGITAL CONVERTER CHARACTERISTICS Parameter Diode Source Current Diode Source Current High Current to Low Current Ratio ANALOG TO DIGITAL CONVERTER CHARACTERISTICS Symbol Parameter TUE Total Unadjusted Error(Note 11) Resolution DNL Differential Non-linearity Power Supply Sensitivity Input Resistance, all analog inputs ...
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AC Electrical Characteristics The following specification apply for =0˚ =85˚C; all other limits MIN MAX specification revision 0.98. Please refer to that speciation for further details. ...
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PIN Pin Pin # Name Circuit GND SWD A 5 ADD A 6 +1. + D2+ ...
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Timing Diagrams FIGURE 1. Timing for Data Bits 0, 1 and Start Bit. See Section 1.2 "SensorPath BIT SIGNALING" for further details. www.national.com 8 20068404 ...
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Timing Diagrams (Continued) FIGURE 2. Timing for Attention Request and Reset. See Section 1.2 "SensorPath BIT SIGNALING" for further details. 9 20068405 www.national.com ...
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... The digitized data can be retrieved over a simple single-wire interface called SensorPath. Sensor- Path has been defined by National Semiconductor and is optimized for hardware monitoring. National offers a royalty- free license in connection with its intellectual property rights in the SensorPath bus ...
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Functional Description that begin with the label Mout_ depict a drive by the master. Signal labels that begin with the label Slv_ depict the drive by the LM40. All other signals show what would be seen when probing SWD ...
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Functional Description 1.3.2 Read Transaction During a read transaction, the master reads data from a register at a specified address within a slave. A read trans- action begins with a Start Bit and ends with an ACK bit, as ...
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Functional Description • Data Bits This is the data written to the LM40 register, are driven by the master. Data is transferred serially with the most significant bit first. The number of data bits may vary from one address ...
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Functional Description All devices (master or slave) must monitor the bus for an Attention Request signal. The following notes clarify the intended system operation that uses the Attention Request Indication. • Masters are expected to use the attention request ...
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Register Set 2.1 REGISTER SET SUMMARY P Bit Register R/ O Reg Add 15 Name W R MSb Val 000 000 Device R * 00h Number 000 001 Manufacturer R 100Bh 0 01h ID 000 010 Device ID R ...
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... Register R/ O Add Name W R MSb Val Manufacturer 000 001 R 100Bh ID The manufacturer ID matches that assigned to National Semiconductor by the PCI SIG. This register may be used to identify the manufacturer of the device in order to perform manufacturer specific operations. www.national.com Bit 7 Bit 6 Bit Val Reserved ...
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Register Set (Continued) 2.5 DEVICE ID (Addr: 000 010; 02h) P Bit Reg Register Add Name W R MSb Val 000 010 Device ID R 22h 0 The device ID is defined by the manufacturer of ...
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Register Set (Continued) Bit Type 7 RO BER (Bus Error) This bit is set when the device either generates, or receives an error indication in the ACK bit of the transaction (i.e., no-acknowledge). BER is cleared by Device Reset ...
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Register Set (Continued) The minimum scan rate is recommended to be 4Hz (i.e. the measurement data is updated at least once in 250 ms), see Section 2.11 for further details. In Low-Power Mode, the scan rate is four times ...
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Register Set (Continued) 2.9.3 Temperature Data Readout (Addr: 001 001; 09h) P Reg Register R/ O Add Name W R MSb Val Local Temperature Data Readout MSb 001 001 R Processor/ Sign Remote Temperature Data Readout Bit Type 0 ...
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Register Set (Continued) Temperature - 40 ˚C -255.5 ˚C -256 ˚C 2.9.4 Temperature Control (Addr: 001 010; 0Ah) This register is set to the reset value by a Device Reset. P Bit Reg Register Add Name ...
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Register Set (Continued) result is ready before the previous result has been read, the new results overwrites the previous result and the Error Function 2 flag (ERF2) for the Voltage-Only function in the Device Status register is set (indicating ...
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Register Set (Continued) Input Voltage for Nominal Sensor Reading Number (code 384 or (SNUM) Voltage Input 180h) 0 +2.5V 2.5V 1 +1.2V 1.2V 2 +3.3V_SBY 3.3V (V +12V 12V 2.10.4 Voltage Control (Addr: 010 010; ...
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Register Set (Continued) Bit Type 7-2 RO Reserved. Will always read "0". LowPwr *Fastest: 2x7.5ms(remote) + 7.5msec (local) + 5x1.42msec (voltage) = 29.6 ms total The sensor conversion rate is controlled ...
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Application Hints (Continued) 3.1 DIODE NON-IDEALITY 3.1.1 Diode Non-Ideality Factor Effect on Accuracy When a transistor is connected as a diode, the following relationship holds for variables and I BE where: −19 • 1.6x10 ...
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Application Hints 3. Ideally, the LM40 should be placed within 10cm of the Processor diode pins with the traces being as straight, short and identical as possible. Trace resistance of 0.7Ω can cause as much as 1˚C of error. ...
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... BANNED SUBSTANCE COMPLIANCE National Semiconductor certifies that the products and packing materials meet the provisions of the Customer Products Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain no ‘‘Banned Substances’’ as defined in CSP-9-111S2. ...