lm80cimtx-5 National Semiconductor Corporation, lm80cimtx-5 Datasheet
lm80cimtx-5
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lm80cimtx-5 Summary of contents
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... Chassis Intrusion Detector input Typical Application # Indicates Active Low (“Not” ® registered trademark of the Philips Corporation. © 2001 National Semiconductor Corporation n WATCHDOG comparison of all monitored values n Separate input to show status in Interrupt Status Register of additional external temperature sensors such as the LM56 or LM75 2 ...
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... T +125˚C A Order Number Device Marking 1 LM80CIMT-3 LM80CIMT-3 2 LM80CIMTX-3 1 LM80CIMT-5 LM80CIMT-5 2 LM80CIMTX-5 1 Note: -Rail transport media, 62 parts per rail 2 -Tape and reel transport media, 3400 parts per reel Block Diagram Pin Descriptions Pin Pin Number Name(s) Number of Pins INT_IN 1 ...
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Pin Descriptions (Continued) Pin Pin Number Name(s) Number of Pins FAN1-FAN2 4-5 2 BTI (Chassis 7 1 Intrusion) GND (+2. +5.75V) INT 10 1 GPO (Power 11 1 Switch Bypass) ...
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Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. + Positive Supply Voltage (V ) Voltage on Any Input or Output Pin Ground Difference (GND - GNDA) Input ...
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DC Electrical Characteristics The following specifications apply for +2.8 V IN0-IN6 unless otherwise specified. Boldface limits apply for T S 25˚C.(Note 7) Symbol Parameter FAN RPM-to-DIGITAL CONVERTER Fan RPM Error Full-scale Count FAN1 and FAN2 Nominal ...
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DC Electrical Characteristics The following specifications apply for +2.8 V IN0-IN6 unless otherwise specified. Boldface limits apply for T S 25˚C.(Note 7) Symbol Parameter BTI Digital Input I Logical “1” Input Current IN(1) I Logical “0” ...
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AC Electrical Characteristics Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is functional, but do not guarantee specific performance limits. For guaranteed specifications and test ...
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Test Circuit Functional Description 1.0 GENERAL DESCRIPTION The LM80 provides 7 analog inputs, a temperature sensor, a Delta-Sigma ADC (Analog-to-Digital Converter), 2 fan speed counters, WATCHDOG registers, and a variety of inputs and outputs on a single chip. A two ...
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Functional Description 2.0 INTERFACE (Continued) FIGURE 4. LM80 Register Structure 9 DS100040-7 www.national.com ...
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Functional Description 2.1 Internal Registers of the LM80 TABLE 1. The internal registers and their corresponding internal LM80 address is as follows: Register LM80 Internal Hex Address (This is the data to be written to the Address Register) Configuration Register ...
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Functional Description 2.2 Serial Bus Interface (a) Serial Bus Write to the Internal Address Register followed by the Data Byte (b) Serial Bus Write to the Internal Address Register Only (c) Serial Bus Read from a Register with the Internal ...
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Functional Description 3.0 USING THE LM80 3.1 Power On When power is first applied, the LM80 performs a “power on reset” on several of its registers. The power on condition of registers is shown in Table 1 . Registers whose ...
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Functional Description A typical application, such as is shown in Figure 6 , might select the input voltage divider to provide 1.9V at the analog inputs of the LM80. This is sufficiently high for good resolu- tion of the voltage, ...
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Functional Description 6.0 FAN INPUTS Inputs are provided for signals from fans equipped with tachometer outputs. These are logic-level inputs with an + approximate threshold of V /2. Signal conditioning in the LM80 accommodates the slow rise and fall times ...
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Functional Description (a) Fan with Tach Pull-Up to +5V (c) Fan with Tach Pull-Up to +12V and Diode Clamp Counts are based on 2 pulses per revolution tachometer outputs. RPM Time per Revolution 4400 13.64 ms 3080 19.48 ms 2640 ...
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Functional Description 7.0 TEMPERATURE MEASUREMENT SYSTEM The LM80 bandgap type temperature sensor and ADC per- form 9-bit or a 12-bit two’s-complement conversions of the temperature. An 8-bit digital comparator is also incorporated that compares the readings to the user-programmable Hot ...
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Functional Description By default Temperature Register data is represented by a 9-bit two’s complement digital word with the LSB having a resolution of 0.5˚C: Temperature Digital Output Binary +125˚C 0 1111 1010 +25˚C 0 0011 0010 +1.5˚C 0 0000 0011 ...
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Functional Description www.national.com (Continued) 18 ...
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Functional Description 8.0 THE LM80 INTERRUPT STRUCTURE Figure 10 depicts the Interrupt Structure of the LM80. The LM80 can generate Interrupts as a result of each of its internal WATCHDOG registers on the analog, temperature, and fan inputs. 8.1 INTERRUPT ...
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Functional Description • INT_IN - This active low Interrupt merely provides a way to chain the INT (Interrupt) from other devices through the LM80 to the processor. 8.2 INTERRUPT OUTPUTS All Interrupts are indicated in the two Interrupt Status Reg- ...
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Functional Description 11.0 FAN MANUFACTURERS Manufacturers of cooling fans with tachometer outputs are listed below: NMB Tech 9730 Independence Ave. Chatsworth, California 91311 818 341-3355 818 341-8207 Model Num- Frame Size ber 2408NL 2.36 in sq. X 0.79 in (60 ...
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Functional Description 12.0 REGISTERS AND RAM 12.1 Address Register The main register is the ADDRESS Register. The bit designations are as follows: Bit Name Read/ Write 7-0 Address Read/Write Pointer Bit 7 Bit 12.2 Address Pointer Index ...
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Functional Description 12.3 Configuration Register — Address 00h < > Power on default 7:0 = 00001000 binary Bit Name Read/ Write 0 Start Read/Write 1 INT Enable Read/Write 2 INT polarity Read/Write select 3 INT_Clear Read/Write 4 RESET Read/Write 5 ...
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Functional Description 12.4 Interrupt Status Register 1 — Address 01h < > Power on default 7:0 = 0000 0000 binary Bit Name Read/Write 0 IN0 Read Only 1 IN1 Read Only 2 IN2 Read Only 3 IN3 Read Only 4 ...
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Functional Description 12.7 Interrupt Mask Register 2 — Address 04h < > Power on default 7:0 = 0000 0000 binary Bit Name Read/ Write 0 Hot Temperature Read/Write 1 BTI Read/Write 2 FAN1 Read/Write 3 FAN2 Read/Write 4 CI (Chassis ...
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Functional Description 12.8 Fan Divisor Register/RST_OUT/OS — Address 05h < > < Power on – 7:4 is 0101, and 3:0 Bit Name Read/Write 0 FAN1 Mode Read/Write Select 1 FAN2 Mode Read/Write Select 2-3 FAN1 RPM Read/Write Control 4-5 FAN2 ...
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Functional Description 12.10 Value RAM — Address 20h–3Fh Address A7–A0 20h IN0 reading 21h IN1 reading 22h IN2 reading 23h IN3 reading 24h IN4 reading 25h IN5 reading 26h IN6 reading 27h Temperature reading 28h FAN1 reading Note: This location ...
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Typical Application FIGURE 11. In this PC application the LM80 monitors temperature, fan speed for 2 fans, and 7 power supply voltages. It also monitors an optical chassis intrusion detector. www.national.com 28 DS100040-19 ...
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... Physical Dimensions Order Number LM80CIMT-3, LM80CIMTX-3, LM80CIMTX-5 or LM80CIMT-5 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. Life support devices or systems are devices or ...