DS1780E Maxim Integrated Products, DS1780E Datasheet
DS1780E
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DS1780E Summary of contents
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... +2 CCP2 GNDA 12 13 DS1780E+ - Address Input / NAND Output - Address Input - 2-Wire Serial Data Input/Output - 2-Wire Serial Clock - Tachometer Inputs - Chassis Intrusion Detector Input - Digital Ground - Power Supply Voltage (2.8V to 5.75V) - Hardware Interrupt output - DAC output / NAND TREE Input - Remote System Reset ...
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DESCRIPTION The DS1780 is a highly integrated system instrumentation monitor ideal for use in personal computers, or any microprocessor-based system. It monitors ambient temperature, six power supply voltages, and the speed of two fans. Fan speed can also be controlled ...
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OVERVIEW A block diagram of the DS1780 is shown in Figure 1. The DS1780 provides six analog inputs, an analog output, five digital inputs, two fan speed inputs, a temperature sensor, and interrupt registers on a single chip, which communicates ...
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A CHS (Chassis Intrusion) digital input is provided. The Chassis Intrusion input is designed to accept an active high signal from an external circuit that latches when the case is removed from the computer; this pin is a dual purpose ...
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INTERNAL ADDRESS REGISTER MAP Table 2 REGISTER Configuration Register Interrupt (INT) Status Register 1 Interrupt (INT) Status Register 2 Interrupt (INT) Mask Register 1 Interrupt (INT) Mask Register 2 Chassis Intrusion Clear Register VID Register Serial Address Register VID4 Register ...
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SERIAL COMMUNICATION WITH THE DS1780 Figure 2 OPERATION - Power-on Applying power to the DS1780 causes a reset of several of the registers. Power-on conditions of the registers are shown in Table 2 above. Some registers have indeterminate power-on ...
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Software Reset - This condition is generated by writing bit 4 of the configuration register. It has no effect on DS1780 register contents. It will however pull the duration (minimum). When the clear itself. ...
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DS1780 MONITORING ORDER Table 3 If conversions are terminated by either of the methods described in the “OPERATION - Configuration Register” section, the current “round-robin” loop will be completed and the results stored in RAM. Monitoring will then terminate. When ...
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The worse such accident would be connecting -12V to +12V; a total of 24V difference, with the series resistors this would draw a maximum of approximately 24 ma. The internal scaling factor depends upon the particular input. The +12V inputs ...
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MIN REF -(V MAX REF 1 2 REF If the +2.5V /+ ...
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V diode to clamp the input level. Tables 7 and 8 describe the format of the data stored in the FAN reading registers (Internal Address Registers 28h and 29h). FAN TACHOMETER INPUT OPTIONS Figure 3 ...
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OPERATION - Interrupts An external interrupt can come from the following sources. While the label suggests a specific type or source of interrupt, this label is not a restriction on the usage; it could come from any desired source. 1. ...
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One-time Interrupt mode: Exceeding hot temperature limit causes an SMI that will remain active indefinitely until reset by reading Interrupt Status Register 1 or cleared by the INT_Clear bit in the Configuration register. Once an SMI event has occurred ...
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TEMPERATURE INTERRUPT MODE ILLUSTRATION Figure 4 SAMPLE CHASSIS INTRUSION DETECTOR/LATCH Figure ...
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OPERATION - Analog Output The DS1780 has a single analog output from a unsigned 8-bit D/A which produces 0-1.25 volts; this is amplified and scaled with external circuitry such as a op-amp and transistor to provide fan speed control. This ...
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Note: To properly implement the NAND TREE test on the PCB, no pins listed in the tree should be connected directly to power or ground pin is needed to configure as a permanent low such as an address, ...
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CONFIGURATION REGISTER (ADDRESS 0X40; POWER-UP DEFAULT = 08h) Table 10.2 BIT NAME R/W Logic 1 enables startup of measurement loop, logic 0 places the DS1780 in standby mode. Caution: The 0 START R/W interrupt has occurred (see “ scanning begins. ...
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INTERRUPT INT STATUS REGISTER 2 (ADDRESS 0X42; POWER-UP DEFAULT=00h) Table 10.4 BIT NAME R/W 0 +12V_Error indicates a High or Low limit has been exceeded. -12V indicates a High or Low limit has ...
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RESERVED REGISTER (ADDRESS 0X45; POWER-UP DEFAULT=00h) Table 10.7 BIT NAME R/W RESERVED R/W Undefined (Power On = 00h). <7:0> CHASSIS INTRUSION CLEAR REGISTER (ADDRESS 0X46; POWER-UP DEFAULT=00h) Table 10.8 BIT NAME R/W 0-6 RESERVED R/W Undefined (Power On = 00h). ...
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TEMPERATURE CONFIGURATION REGISTER (ADDRESS Ox4B; POWER-UP DEFAULT = 01h) Table 10.12 BIT NAME R/W If Bits 0 and Bits 1 of this register are both 0 or both 1, this selects the default interrupt mode which gives the user an ...
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VALUE RAM (ADDRESS 0x15h - 0x3Dh) Table 10.15 ADDRESS <A7:A0>h R/W 20h 21h 22h 23h 24h 25h 26h 27h 28h 29h 2Ah R/W 2Bh R/W 2Ch R/W 2Dh R/W 2Eh R/W 2Fh R/W 30h R/W 31h R/W 32h R/W 33h ...
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This register will latch an 8-bit value into an R-2R D/A to provide a range of 0-1.25 volts; accuracy can be ±5% or more. 5. This location will contain the company identification number which will be used by software ...
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DC ELECTRICAL CHARACTERISTICS Power Supply PARAMETER SYMBOL Supply Current ELECTRICAL CHARACTERISTICS: Temperature-to-Digital Converter PARAMETER SYMBOL Thermometer Error T ERR Resolution DC ELECTRICAL CHARACTERISTICS: Voltage-to-Digital Converter PARAMETER SYMBOL ADC Resolution Voltage to Digital Conversion Resolution (See Voltage A/D ...
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DC ELECTRICAL CHARACTERISTICS: Fan RPM-to-Digital Converter PARAMETER SYMBOL Accuracy Full scale count FAN1 & FAN2 Normal Input RPM Internal Oscillator Frequency DC ELECTRICAL CHARACTERISTICS: Analog Output V OUT PARAMETER SYMBOL DAC Resolution Voltage Range Error DAC Output Current I OUT ...
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DC ELECTRICAL CHARACTERISTICS: Open-drain Digital Outputs: PARAMETER SYMBOL Logical 0 V OUT Output Voltage High Level I OH Output Current Active Pulse Width DC ELECTRICAL CHARACTERISTICS: Open-drain 2-Wire Bus Output: SDA PARAMETER SYMBOL Logical 0 V OUT Output Voltage High ...
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DC ELECTRICAL CHARACTERISTICS: All Digital Inputs PARAMETER SYMBOL Logical Input Current Logical Input Current Input Capacitance C AC ELECTRICAL CHARACTERISTICS: 2-Wire Interface PARAMETER SYMBOL SCL Clock Period t Data In Setup t Time to ...
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... DS1780 (See Note) DS1780E+T&R DS1780 (See Note) DS1780E DS1780 DS1780E/T&R DS1780 Note : A "+" symbol will also be marked on the package near the Pin 1 indicator £ 5.75V, unless otherwise stated as a condition. Typical values represent £ 5.5V, unless otherwise stated as a condition. ...
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DS1780 24 LD. TSSOP DIM MIN MAX A - 1. 0.75 1.05 0.09 0.18 c 0° 8° phi L 0.50 0.70 e1 0.65 BSC 0.18 0.30 B 7.55 8. 4.40 NOM G 0.25 REF ...