LM87CIMT/NOPB National Semiconductor, LM87CIMT/NOPB Datasheet
LM87CIMT/NOPB
Specifications of LM87CIMT/NOPB
*LM87CIMT/NOPB
LM87CIMT
Related parts for LM87CIMT/NOPB
LM87CIMT/NOPB Summary of contents
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... SMBus ™ trademark of Intel Corporation. © 2010 National Semiconductor Corporation LM87 ■ 2 inputs selectable for fan speed or voltage monitoring ■ 8-bit DAC output for controlling fan speed ■ ...
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Block Diagram Pin Descriptions Pin Pin Number Name(s) Number of Pins ADD/NTEST_OUT 1 THERM# 2 SMBData 3 SMBCLK 4 FAN1/AIN1- 5-6 FAN2/AIN2 www.national.com Type This pin normally functions as a three-state input that controls the two LSBs of the Serial ...
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Pin Pin Number Name(s) Number of Pins CI 7 GND (+2 +3 INT# /ALERT# 10 DACOut/NTEST_IN 11 RESET# 12 D1− 13 D1+ 14 +12Vin 15 +5Vin 16 Vccp2/D2− 17 +2.5Vin/D2+ 18 Vccp1 19 ...
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... Absolute Maximum Ratings 2) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Positive Supply Voltage ( Voltage on Any Input or Output Pin: +12Vin ADD/NTESTOUT, DACOut/ NTEST_IN, AIN1, AIN2 All other pins Input Current at any Pin ...
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Symbol Parameter DAC Error R Output Load Resistance L C Output Load Capacitance L FAN RPM-TO-DIGITAL CONVERTER Fan RPM Error Full-scale Count FAN1 and FAN2 Nominal Input RPM (See Section 6.0) DIGITAL OUTPUTS (NTEST_OUT) V Logical “1” Output Voltage OUT(1) ...
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... P Note 6: The human body model is a 100 pF capacitor discharged through a 1.5 kΩ resistor into each pin. Note 7: See the section titled “Surface Mount” found in any post 1986 National Semiconductor Linear Data Book for other methods of soldering surface mount devices. ...
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Pin Name INT FAN1–FAN2 SMBCLK SMBData RESET ADD/NTEST_OUT indicates that the diode exists. ...
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Test Circuit Typical Performance Characteristics Functional Description 1.0 GENERAL DESCRIPTION The LM87 provides 7 analog inputs, an internal junction type temperature sensor, two remote junction temperature sens- ing channels, a Delta-Sigma ADC (Analog-to-Digital Convert- er), a DAC output, 2 fan ...
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An 8 bit DAC with 2.5 V output voltage range can be used for control of fan speed. The LM87 has several internal registers, as shown in 4, Table 1 ...
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INTERFACE www.national.com FIGURE 4. LM87 Register Structure 10 10099507 ...
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... Defaults to full scale DAC setting. 1Ah-3Fh (See Section 13.18) Contains: monitoring results (temperature, voltages, fan counts), WATCHDOG limits, and Company/Stepping IDs 3Eh 0000 0010 This designates the National Semiconductor LM87. 3Fh 0000 0110 Revisions of this device will start with 1 and increment by one. 40h 0000 1000 ...
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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 Address Register ...
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All of these communications are depicted in the Serial Bus Interface Timing Diagrams as shown in ple shown corresponds to the ADD pin tied to Vcc, so XY=01 and the resulting LM87 address is 0101101. Serial Bus Timeout can be ...
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Bit 4 of the Channel Mode Register, when set to 1, enables pin active low (IRQ0) interrupt input. When set to 0, this input is disabled as an IRQ interrupt. Bit 5 of the Channel Mode Register, ...
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The resistors were selected by setting kΩ and then calculating R1 using the following equation mum negative input voltage the positive pullup voltage [(1.25V − ÷ ...
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Fan with Tach Pull-Up to +12V and Diode Clamp 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 Divide by ...
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Scale for Clarity) FIGURE 8. 8-bit Temperature-to-Digital Transfer Function 8.1 Temperature Data Format Temperature data can be read from the Temperature, T setpoint, T setpoint, and Hardware Temperature limit reg- LOW isters; and written to the T setpoint, T ...
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That is equally to the D+ and D− lines. 4. Avoid routing diode traces in close proximity to power supply switching ...
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WATCHDOG LIMIT COMPARISONS AND INTERRUPT STRUCTURE Figure 10 depicts the Interrupt Structure of the LM87. The LM87 can generate Interrupts as a result of each of its internal WATCHDOG registers on the analog, temperature, and fan inputs. External Interrupts ...
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THERM# input is deactivated and the DAC setting register is unaffected by the THERM# input condition. • IRQ0-2: These are active low inputs from any type of external interrupt source. If enabled via the Channel Mode Register (16h) the ...
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Reading the Interrupt Status Registers will clear the status bit and will cause INT deasserted. If the external signal continues to pull THERM# low, the Interrupt Status Bit will be reset at the completion of the next conversion ...
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RESET# I/O RESET# is intended to provide a master reset to devices connected to this line. Setting Bit 4 in Configuration Register 1 high outputs (minimum) low pulse on this line, at the end of which ...
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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 Number Frame Size 2408NL 2.36 in sq. X 0.79 in (60 mm sq. X ...
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... Always set to 00h 70 °C Default - <7:0>=0100 0110 - User adjustable 85 °C Default - <7:0>=0101 0101 - User adjustable See Section 13.18 for details. Address 19h default=1111 1111 This designates the National Semiconductor LM87. Revisions of this device will start with 1 and increment by one. Bit 0 A0 ...
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Test Register—Address 15h Power on default – <7:0> = 00000000 binary Bit Name Read/Write 0 Shutdown Read/Write A one places the LM87 in a lower power "Shutdown" mode. 1 Reserved Read/Write 2 Reserved Read/Write 3 Reserved Read/Write 4 Reserved ...
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Configuration Register 1—Address 40h 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 ...
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Interrupt Status Register 2—Address 42h Power on default – <7:0> = 0000 0000 binary Bit Name Read/Write 0 +12Vin Read Only 1 Vccp2 Read Only 2 Reserved Read Only 3 Reserved Read Only 4 CI Read Only 5 THERM# ...
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VID0-3/Fan Divisor Register—Address 47h Power on default – <7:4> is 0101, and <3:0>is mapped to VID <3:0> Bit Name Read/Write 0-3 VID <3:0> Read Only 4-5 FAN1 RPM Read/Write Control 6-7 FAN2 RPM Read/Write Control 13.13 VID4 Register—Address 49h ...
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Bit Name Read Only 6 FAN1/AIN1 Read Only A one indicates the fan count limit has been exceeded or an AIN1 High or Low limit has been exceeded. 7 FAN2/AIN2 Read Only A one indicates the fan count limit has ...
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... Note the number of counts of the internal clock for the Low Limit of the fan speed. 3Dh Reserved 3Eh Company Identification. The number in this register identifies National Semiconductor LM87 (0000 0010) 3Fh Stepping Register LM87 revision number 06h(0000 0110) Note: Setting all ones to the high limits for voltages and fans (0111 1111 binary for temperature) means interrupts will never be generated except the case when voltages go below the low limits ...
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Typical Application FIGURE 13. In this PC application the LM87 monitors temperature, fan speed for 2 fans, and 6 power supply voltages. It also monitors an optical chassis intrusion detector. The LM87 provides a DAC output that can be used ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 24-Lead TSSOP Order Number LM87CIMT NS Package Number MTC24B 32 ...
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Notes 33 www.national.com ...
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... For more National Semiconductor product information and proven design tools, visit the following Web sites at: www.national.com Products Amplifiers www.national.com/amplifiers Audio www.national.com/audio Clock and Timing www.national.com/timing Data Converters www.national.com/adc Interface www.national.com/interface LVDS www.national.com/lvds Power Management www.national.com/power Switching Regulators www.national.com/switchers LDOs www.national.com/ldo LED Lighting www ...