LM78CCVF-J National Semiconductor, LM78CCVF-J Datasheet
LM78CCVF-J
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LM78CCVF-J Summary of contents
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... Electronic Test Equipment and Instrumentation Typical Application # indicates Active Low (”Not“ ® registered trademark of the Phillips Corporation. © 2001 National Semiconductor Corporation Features n Temperature sensing n 5 positive voltage inputs amps for negative voltage monitoring n 3 fan speed monitoring inputs n Input for additional temperature sensors ...
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... Ordering Information Temperature Range −10˚C T +100˚C A Order Number Device Marking LM78CCVF LM78CCVF-J Block Diagram www.national.com Connection Diagram Package VGZ44A 2 DS012873-2 DS012873-3 ...
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Pin Descriptions Pin Pin Number Name(s) Number of Pins IORD 1 1 IOWR 2 1 SYSCLK 3 1 D7–D0 4– (+5V GNDD 13 1 SMI__IN 14 1 Chassis 15 1 Intrusion Power 16 1 Switch ...
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Pin Descriptions (Continued) Pin Pin Number Name(s) Number of Pins A2–A0 41– TOTAL PINS 44 www.national.com Type Digital Input The three lowest order bits of the 16-bit ISA Address Bus. A0 corresponds to the lowest order ...
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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 ( Voltage on Any Input or Output Pin Ground Difference (GNDD–GNDA) Input Current at any Pin (Note 3) Package Input Current (Note 3) ...
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DC Electrical Characteristics The following specifications apply for +4.25 V fied. Boldface limits apply for Symbol Parameter FAN RPM-TO-DIGITAL CONVERTER FAN1 and FAN2 Nominal Input RPM (See Section 6.0) FAN3 Design Nominal Input RPM Internal Clock ...
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AC Electrical Characteristics +5.75 V unless otherwise specified. Boldface limits apply for T DC 25˚C. Symbol Parameter ISA TIMING CHARACTERISTICS f System Clock (SYSCLK) Input Frequency SYSCLK t (setup) CS Active to IORD/IOWR Active CS t (hold) IORD/IOWR Inactive to ...
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AC Electrical Characteristics unless otherwise specified. Boldface limits apply for T Symbol ISA READ TIMING t (setup) Data Valid to IORD Inactive SDRD t (hold) IORD Inactive to Data Invalid SDRD t (setup) IORD Active to Rising Edge of SYSCLK ...
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AC Electrical Characteristics unless otherwise specified. Boldface limits apply for T Symbol Parameter SERIAL BUS TIMING CHARACTERISTICS t SCL (Clock) Period 1 t Data In Setup Time to SCL High 2 t Data Out Stable After SCL Low 3 t ...
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... Note 5: The human body model is a 100 pF capacitor discharged through a 1.5 k directly into each pin. Note 6: See the section titled “Surface Mount” found in any post 1986 National Semiconductor Linear Data Book for other methods of soldering surface mount devices. Note 7: Each input and output is protected by a nominal 6.5V breakdown voltage zener diode to GND; as shown below, input voltage magnitude up to 0.3V above ...
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Test Circuit Functional Description 1.0 GENERAL DESCRIPTION The LM78 provides 7 analog inputs, a temperature sensor, a Delta-Sigma ADC (Analog-to-Digital Converter), 3 fan speed counters, WATCHDOG registers, and a variety of inputs and outputs on a single chip. Interfaces are ...
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Functional Description 2.0 INTERFACE The LM78 only decodes the three lowest address bits on the ISA bus. Referring to the ISA bus timing diagrams in Figure 1 and Figure 2 , the Chip Select Input, CS, should be taken low ...
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Functional Description (Continued) FIGURE 6. LM78 Register Structure 13 DS012873-9 www.national.com ...
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Functional Description 2.1 Internal Registers of the LM78 TABLE 1. The internal registers and their corresponding internal LM78 address is as follows: Register LM78 Internal Hex (This is the data to be written to Port x5h) Configuration Register Interrupt Status ...
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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 LM78 3.1 Power On When power is first applied, the LM78 performs a “power on reset” on several of its registers. The power on condition of registers in shown in Table I. Registers whose power ...
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Functional Description A typical application, such as is shown in Figure 8 , might select the input voltage divider to provide 3V at the analog inputs of the LM78. This is sufficiently high for good resolu- tion of the voltage, ...
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Functional Description Voltage Measurements (V +2.50V +3.30V +5V +12V −12V −5V FIGURE 8. Input Examples. Resistor Values Shown Provide Approximately 3V at the Analog Inputs www.national.com (Continued NONE 0 ...
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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 LM78 bandgap type temperature sensor and ADC per- form 8-bit two’s-complement conversions of the tempera- ture. A digital comparator is also incorporated that compares the readings to the user-programmable Overtemperature setpoint and Hysteresis ...
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Functional Description 8.0 THE LM78 INTERRUPT STRUCTURE Figure 12 depicts the Interrupt Structure of the LM78. The LM78 can generate Interrupts as a result of each of its internal WATCHDOG registers on the analog, temperature, and fan inputs. Overflow of ...
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Functional Description • Chassis Intrusion: This is an active high interrupt from any type of device that detects and captures chassis intrusion violations. This could be accomplished me- chanically, optically, or electrically, and circuitry external to the LM78 is expected ...
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Functional Description 12.0 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 REGISTERS AND RAM 13.1 Address Register (Port x5h) The main register is the ADDRESS Register located at Port x5h. The bit designations are as follows: Bit Name Read/ Write 6-0 Address Read/Write Pointer 7 Busy Read Only Bit ...
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Functional Description 13.2 Data Register (Port x6h) < > Power on default 7:0 = 00h Bit Name Read/ Write 7–0 Data Read/Write Data to be read from written to RAM and Register. 13.3 Configuration Register — Address ...
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Functional Description 13.4 Interrupt Status Register 1 — Address 41h < > Power on default 7:0 = 00h Bit Name Read/Write 0 IN0 Read Only 1 IN1 Read Only 2 IN2 Read Only 3 IN3 Read Only 4 Temperature Read ...
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Functional Description 13.7 SMI Mask Register 2 — Address 44h < > Power on default 7:0 = 00h Bit Name Read/ Write 0 IN4 Read/Write 1 -IN5 Read/Write 2 -IN6 Read/Write 3 FAN3 Read/Write 4 Chassis Intrusion Read/Write 5 FIFO ...
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Functional Description 13.10 VID/Fan Divisor Register — Address 47h < > < Power on – 7:4 is 0101, and 3:0 Bit Name Read/Write < > 3-0 VID 3:0 Read Only 5-4 FAN1 RPM Read/Write Control 7-6 FAN2 RPM Read/Write Control ...
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Functional Description Address A6–A0 with Address A6–A0 Auto-Increment 29h 69h 2Ah 6Ah 2Bh 6Bh 2Ch 6Ch 2Dh 6Dh 2Eh 6Eh 2Fh 6Fh 30h 70h 31h 71h 32h 72h 33h 73h 34h 74h 35h 75h 36h 76h 37h 77h 38h 78h ...
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Typical Application FIGURE 13. In this PC application the LM78 monitors temperature, fan speed for 3 fans, and 7 power supply voltages. It also monitors the O.S. Output LM75 digital temperature sensors as well www.national.com as ...
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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) unless otherwise noted Order Number LM78CCVF-J NS Package Number VGZ44A 2 ...