lm41cimtx National Semiconductor Corporation, lm41cimtx Datasheet
lm41cimtx
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lm41cimtx Summary of contents
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... SensorPath Interface — 2 hardware programmable addresses n Voltage Monitoring — 9-bit Σ∆ ADC Typical Application SensorPath is a trademark of National Semiconductor Corporation ™ © 2004 National Semiconductor Corporation — Internal scaling resistors for all inputs — Monitors +1.2V, +2 and + Temperature Sensing — ...
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... +5V 12 +12V www.national.com Order Number LM41CIMT LM41CIMTX 20070302 Description Typical Connection No Connect May be tied to V+, GND or left floating. Do not tie active signals to pin 10. Ground System ground Positive power supply pin as well Connected system 3.3 V standby power and as a +3.3V voltage monitor to a 0.1 µ ...
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Block Diagram 3 20070303 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 D+ −0 (V+ + 0.05 V) Voltage ...
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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. +2. +5V ...
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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 20070304 ...
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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 20070305 www.national.com ...
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Typical Performance Characteristics Remote Diode Temperature Reading Sensitivity to Diode Filter Capacitance 1.0 Functional Description The LM41 hardware monitor measures temperature zones and 5 power supply voltages. The LM41 uses a ∆V temperature sensing method. A differential ...
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Functional Description Signal labels that begin with the label Slv_ depict the drive by the LM41. All other signals show what would be seen when probing SWD for a particular function (e.g. "Master Wr 0" is the Master transmitting ...
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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 LM41 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 Reg Register Add 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 Set (Continued) * Depends on state of ADD pins see Section 2.3 "Device Number". 2.2 DEVICE RESET OPERATION A Device Reset operation is performed in the following conditions: • At device power-up. • When the Reset bit in ...
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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 24h 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 Reserved. ...
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Register Set (Continued) Temperature -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 W R MSb ...
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Register Set (Continued) Function Event The Voltage-Only Measurement function generates a Function Event to the master whenever a conversion cycle is completed and new data is stored in the Readout register. When the new data is stored into the ...
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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 1-0 RO CR0 and CR1 (Conversion Rate bits 0 and 1) These bits control the conversion rate of the LM41 for more details see Table Conversion Rate Control and desciption below. Reserved. Will always ...
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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 LM41 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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... 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) Order Number LM41CIMT, or LM41CIMTX, NS Package Number MTC14C 2. A critical component is any component of a life ...