ADT7481ARMZ-001 ON Semiconductor, ADT7481ARMZ-001 Datasheet
ADT7481ARMZ-001
Specifications of ADT7481ARMZ-001
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ADT7481ARMZ-001 Summary of contents
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ADT7481 Dual Channel Temperature Sensor and Overtemperature Alarm The ADT7481 is a 3−channel digital thermometer and under/ over temperature alarm, intended for use in PCs and thermal management systems. It can measure its own ambient temperature or the temperature of ...
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CONVERSION RATE ON−CHIP TEMP SENSOR LOCAL TEMPERATURE VALUE REGISTER D1+ 2 D1– ANALOG 11−BIT A−TO−D 3 MUX CONVERTER D2+ 7 BUSY RUN/STANDBY D2– 8 REMOTE 1 AND 2 TEMP VALUE REGISTERS REMOTE 1 AND 2 TEMP OFFSET REGISTERS EXTERNAL DIODES ...
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PIN ASSIGNMENT Pin No. Mnemonic 1 V Positive Supply D1+ Positive Connection to the Remote 1 Temperature Sensor. 3 D1− Negative Connection to the Remote 1 Temperature Sensor. 4 THERM Open−Drain Output. Requires ...
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ELECTRICAL CHARACTERISTICS Parameter Power Supply Supply Voltage Average Operating Supply Current Undervoltage Lockout Threshold Power−On−Reset Threshold Temperature−To−Digital Converter Local Sensor Accuracy (Note 2) Resolution Remote Diode Sensor Accuracy (Note 2) Resolution Remote Sensor Source Current Conversion ...
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DEV 1 DEV 8 DEV 15 3.0 DEV 2 DEV 9 DEV 16 DEV 3 DEV 10 MEAN DEV 4 DEV 11 HIGH 4S 2.5 DEV 5 DEV 12 LOW 4S DEV 6 DEV 13 2.0 DEV 7 DEV ...
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DEV 2BC 418 416 414 DEV 3BC DEV 4BC 412 410 408 3.0 3.1 3.2 3.3 3.4 V (V) DD Figure 9. Operating Supply Current vs. Voltage 35 DEV 2BC DEV 3BC 30 DEV 4BC ...
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Theory of Operation The ADT7481 is a local and dual remote temperature sensor and over/under temperature alarm. When the ADT7481 is operating normally, the on−board ADC operates in a free−running mode. The analog input multiplexer alternately selects either the on−chip ...
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Table 1. Register Address for the Temperature Values Temperature Register Address, Channel MSBs Local 0x00 Remote 1 0x01 Remote 2 0x30 If Bit 3 of the Configuration 1 register is set to 1, then the Remote 2 temperature values can ...
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Registers The registers in the ADT7481 are eight bits wide. These registers are used to store the results of remote and local temperature measurements, high and low temperature limits, and to configure and control the device. A description of these ...
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Table 6. Conversion Rate/Channel Selector Register (Read Address 0x04, Write Address 0x0A) Bit Mnemonic 7 Averaging Setting this bit to 1 disables averaging of the temperature measurements at the slower conversion rates (averaging cannot take place at the three faster ...
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Table 8. Status Register 2 Bit Assignments Bit Mnemonic Function 7 Res Reserved for Future Use 6 Res Reserved for Future Use 5 Res Reserved for Future Use 4 1 When Remote 2 High R2HIGH Temperature Limit Tripped (Note 1) ...
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Consecutive ALERT Register The value written to this register determines how many out−of−limit measurements must occur before an ALERT is generated. The default value is that one out−of−limit measurement generates an ALERT. The maximum value that can be chosen is ...
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Table 11. List of Registers Read Write Address Address (Hex) (Hex THERM Hysteresis 22 22 Consecutive ALERT 23 N/A Status Register Configuration 2 Register 30 N/A Remote 2 Temperature Value High Byte 31 31 Remote ...
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In read mode, the master device will override the acknowledge bit by pulling the data line high during the low period before the ninth clock pulse. This is known as no acknowledge. The master will then take ...
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When reading data from a register there are two possible scenarios: • If the address pointer register value of the ADT7481 is unknown or not the desired value necessary to set it to the correct value before data ...
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Low Power Standby Mode The ADT7481 can be put into low power standby mode by setting Bit 6 (Mon/STBY bit) of the Configuration 1 register (Read Address 0x03, Write Address 0x09 The ADT7481 operates normally when Bit 6 ...
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TEMPERATURE 100°C 90°C 80°C 70°C 60°C 50°C 40°C ALERT 1 THERM 2 3 Figure 19. Operation of the ALERT and THERM Interrupts • If the measured temperature exceeds the high temperature limit, the ALERT output will assert low. • If ...
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This offset may be programmed to the offset register important to note that if more than one offset must be considered, the algebraic sum of these offsets must be programmed to the offset register ...
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... Package Type ADT7481ARMZ 10-Lead MSOP ADT7481ARMZ-REEL 10-Lead MSOP ADT7481ARMZ-R7 10-Lead MSOP ADT7481ARMZ-001 10-Lead MSOP ADT7481ARMZ-1RL 10-Lead MSOP ADT7481ARMZ-1R7 10-Lead MSOP †For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging Specifications Brochure, BRD8011/D. ...
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... SEATING H PLANE *For additional information on our Pb−Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. Protected by U.S. Patents 5,195,827; 5,867,012, 5,982,221; 6,097,239; 6,133,753; 6,169,442, other patents pending. ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice to any products herein ...