LM80CIMT-3/NOPB National Semiconductor, LM80CIMT-3/NOPB Datasheet
LM80CIMT-3/NOPB
Specifications of LM80CIMT-3/NOPB
*LM80CIMT-3/NOPB
LM80CIMT-3
Related parts for LM80CIMT-3/NOPB
LM80CIMT-3/NOPB Summary of contents
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... WATCHDOG comparison of all monitored values Typical Application # Indicates Active Low (“Not” C® registered trademark of the Philips Corporation. © 2010 National Semiconductor Corporation LM80 ■ Separate input to show status in Interrupt Status Register of additional external temperature sensors such as the LM56 or LM75 ■ ...
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... T +125°C A Order Number Device Marking LM80CIMT-3 1 LM80CIMT-3 LM80CIMTX-3 2 LM80CIMT-5 1 LM80CIMT-5 LM80CIMTX-5 2 Note: 1 -Rail transport media, 62 parts per rail 2 -Tape and reel transport media, 3400 parts per reel Block Diagram www.national.com Connection Diagram Specified NS Power Package Supply ...
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Pin Descriptions Pin Pin Number Name(s) Number of Pins INT_IN 1 1 SDA 2 1 SCL 3 1 FAN1-FAN2 4-5 2 BTI (Chassis 7 1 Intrusion) GND (+2. +5.75V) INT ...
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... Junction to Ambient Thermal Resistance (θ NS Package Number: MTC24B 2000V Supply Voltage (V 125V Ground Difference (|GND − GNDA|) V Voltage Range: IN 215°C ≤ ≤ +3.8 V for LM80CIMT-3, +4. Conditions Interface Inactive and V Interface Inactive and V Shutdown Mode ≤ ≤ −25°C T +125°C A (Note ...
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Symbol Parameter FAN RPM-to-DIGITAL CONVERTER Fan RPM Error Full-scale Count FAN1 and FAN2 Nominal Input RPM (See Section 6.0) Internal Clock Frequency DIGITAL OUTPUTS: A0/NTEST_OUT, INT V Logical “1” Output Voltage OUT(1) V Logical “0” Output Voltage OUT(0) OPEN DRAIN ...
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... GND will not damage the LM80. There are parasitic diodes that exist between the inputs and the power supply rails. Errors in the ADC conversion can occur if these diodes are forward biased by more than 50 mV example conversions indicates that the diode exists. www.national.com ≤ ≤ +3.8 V for LM80CIMT-3, +4. MIN MAX ...
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Pin Name INT_IN CI GPO FAN1–FAN2 SCL SDA RST_OUT/OS Note 8: Typicals are =25°C and represent most likely parametric norm Note 9: Limits are guaranteed to National's AOQL (Average Outgoing Quality Level). Note 10: TUE ...
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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 wire Serial ...
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INTERFACE FIGURE 4. LM80 Register Structure 9 10004007 www.national.com ...
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Internal Registers of the LM80 TABLE 1. The internal registers and their corresponding internal LM80 address is as follows: Register Address (This is the data to be written to the Address Register) Configuration Register Interrupt Status Register 1 Interrupt ...
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Serial Bus Read from a Register with the Internal Address Register Preset to Desired Location The Serial Bus control lines consists of the SDA (serial data), SCL (serial clock) and A0-A1 (address) pins. The LM80 can only operate as ...
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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 power on val- ...
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Then select provide a 1.9V input as show in Figure 6. FIGURE 6. Input Examples. Resistor values shown in table provide approximately 1.9V at the analog inputs. For positive input voltages ...
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Fan with Tach Pull-Up to +12V, or Totem-Pole Output and Resistor Attenuator (d) Fan with Strong Tach Pull-Up or Totem Pole Output and Diode Clamp www.national.com (a) Fan with Tach Pull-Up to +5V (c) Fan with Tach Pull-Up to ...
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Counts are based on 2 pulses per revolution tachometer out- puts. RPM Time per Revolution 4400 13.64 ms 3080 19.48 ms 2640 22.73 ms Mode Select Nominal RPM Time per Revolution Divide by 1 8800 Divide by 2 4400 Divide ...
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Scale for Clarity) FIGURE 9. 12-bit Temperature-to-Digital Transfer Function 7.1 Temperature Data Format Temperature data can be read from the Temperature and T setpoint registers; and written to the hot hyst os os hyst T ...
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Temperature Interrupts There are four Value RAM WATCHDOG limits for the Tem- perature reading that affect the INT and OS outputs of the LM80. They are: Hot Temperature Limit, Hot Temperature Hysteresis Limit, OS Limit, OS Hysteresis Limit. There ...
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www.national.com 18 ...
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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 Inputs External ...
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Interrupt Outputs All Interrupts are indicated in the two Interrupt Status Regis- ters. INT output has two mask registers, and individual masks for each Interrupt. As described in Section 3.3, this hardware Interrupt line can also be enabled/disabled in ...
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REGISTERS AND RAM 12.1 Address Register The main register is the ADDRESS Register. The bit desig- nations are as follows: Bit Name Read/Write 7-0 Address Pointer Read/Write Address of RAM and Registers. See the tables below for detail. Bit ...
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Configuration Register—Address 00h Power on default <7:0> = 00001000 binary Bit Name Read/Write 0 Start Read/Write A one enables startup of monitoring operations, a zero puts the part in standby mode. 1 INT Enable Read/Write A one enables the ...
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Interrupt Status Register 1—Address 01h Power on default <7:0> = 0000 0000 binary Bit Name Read/Write 0 IN0 Read Only A one indicates a High or Low limit has been exceeded. 1 IN1 Read Only A one indicates a ...
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Interrupt Mask Register 2—Address 04h Power on default <7:0> = 0000 0000 binary Bit Name Read/Write 0 Hot Temperature Read/Write A one disables the corresponding interrupt status bit for INT interrupt. 1 BTI Read/Write A one disables the corresponding ...
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Fan Divisor Register/RST_OUT/OS—Address 05h Power on – <7:4> is 0101, and <3:0>is mapped to VID <3:0> Bit Name Read/Write 0 FAN1 Mode Select Read/Write 1 FAN2 Mode Select Read/Write 2-3 FAN1 RPM Read/Write Control 4-5 FAN2 RPM Read/Write Control ...
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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 stores the number of ...
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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. 27 10004019 www.national.com ...
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... Physical Dimensions Order Number LM80CIMT-3, LM80CIMTX-3, LM80CIMTX-5 or LM80CIMT-5 www.national.com inches (millimeters) unless otherwise noted 24-Lead Molded Plastic TSSOP NS Package Number MTC24B 28 ...
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Notes 29 www.national.com ...
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