Rainbow-electronics LM80 Manuel d'utilisateur

LM80Serial Interface ACPI-Compatible Microprocessor SystemHardware MonitorGeneral DescriptionThe LM80 provides 7 positive voltage inputs, temperaturem

Functional Description (Continued)2.1 Internal Registers of the LM80TABLE 1. The internal registers and their corresponding internal LM80 address is a

Functional Description (Continued)2.2 Serial Bus InterfaceThe Serial Bus control lines consists of the SDA (serial data),SCL (serial clock) and A0-A1

Functional Description (Continued)3.0 USING THE LM803.1 Power OnWhen power is first applied, the LM80 performs a “power onreset” on several of its reg

Functional Description (Continued)A typical application, such as is shown inFigure 6, mightselect the input voltage divider to provide 1.9V at the ana

Functional Description (Continued)6.0 FAN INPUTSInputs are provided for signals from fans equipped withtachometer outputs. These are logic-level input

Functional Description (Continued)Counts are based on 2 pulses per revolution tachometer outputs.RPM Time per Revolution Counts for “Divide by 2” Comm

Functional Description (Continued)7.0 TEMPERATURE MEASUREMENT SYSTEMThe LM80 bandgap type temperature sensor and ADC per-form 9-bit or a 12-bit two’s-

Functional Description (Continued)By default Temperature Register data is represented by a9-bit two’s complement digital word with the LSB having ares

Functional Description (Continued)DS100040-17Temperature Interrupt Response Diagram. This diagram does not reflect all the possible variations in the

Functional Description (Continued)8.0 THE LM80 INTERRUPT STRUCTUREFigure 10depicts the Interrupt Structure of the LM80. TheLM80 can generate Interrupt

Ordering InformationTemperature RangeNSPackageNumber−25˚C ≤ TA≤ +125˚C SpecifiedPowerSupplyVoltageOrder Number DeviceMarkingLM80CIMT-31LM80CIMTX-32LM8

Functional Description (Continued)•INT_IN - This active low Interrupt merely provides away to chain the INT (Interrupt) from other devicesthrough the

Functional Description (Continued)11.0 FAN MANUFACTURERSManufacturers of cooling fans with tachometer outputs arelisted below:NMB Tech9730 Independenc

Functional Description (Continued)12.0 REGISTERS AND RAM12.1 Address RegisterThe main register is the ADDRESS Register. The bit designations are as fo

Functional Description (Continued)12.3 Configuration Register—Address 00hPower on default<7:0>= 00001000 binaryBit Name Read/WriteDescription0 S

Functional Description (Continued)12.4 Interrupt Status Register 1—Address 01hPower on default<7:0>= 0000 0000 binaryBit Name Read/Write Descrip

Functional Description (Continued)12.7 Interrupt Mask Register 2—Address 04hPower on default<7:0>= 0000 0000 binaryBit Name Read/WriteDescriptio

Functional Description (Continued)12.8 Fan Divisor Register/RST_OUT/OS — Address 05hPower on –<7:4>is 0101, and<3:0>is mapped to VID<3:

Functional Description (Continued)12.10 Value RAM — Address 20h–3FhAddress A7–A0 Description20h IN0 reading21h IN1 reading22h IN2 reading23h IN3 readi

Typical ApplicationDS100040-19FIGURE 11. In this PC application the LM80 monitors temperature, fan speed for 2 fans, and 7 powersupply voltages. It al

Physical Dimensions inches (millimeters) unless otherwise notedLIFE SUPPORT POLICYNATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENT

Pin Descriptions (Continued)PinName(s)PinNumberNumberof PinsType DescriptionFAN1-FAN2 4-5 2 Digital Inputs 0 to V+fan tachometer inputs.BTI6 1 Digital

Absolute Maximum Ratings (Notes 1, 2)If Military/Aerospace specified devices are required,please contact the National Semiconductor Sales Office/Distr

DC Electrical Characteristics (Continued)The following specifications apply for +2.8 VDC≤V+≤ +3.8 VDCfor LM80CIMT-3, +4.25 VDC≤V+≤ +5.75 VDCfor LM80CI

DC Electrical Characteristics (Continued)The following specifications apply for +2.8 VDC≤V+≤ +3.8 VDCfor LM80CIMT-3, +4.25 VDC≤V+≤ +5.75 VDCfor LM80CI

AC Electrical Characteristics (Continued)Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratin

Test CircuitFunctional Description1.0 GENERAL DESCRIPTIONThe LM80 provides 7 analog inputs, a temperature sensor, aDelta-Sigma ADC (Analog-to-Digital

Functional Description (Continued)2.0 INTERFACEDS100040-7FIGURE 4. LM80 Register StructureLM80www.national.com9