ADT7483AARQZ-R7 ON Semiconductor, ADT7483AARQZ-R7 Datasheet
ADT7483AARQZ-R7
Specifications of ADT7483AARQZ-R7
Related parts for ADT7483AARQZ-R7
ADT7483AARQZ-R7 Summary of contents
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FEATURES 1 local and 2 remote temperature sensors 0.25°C resolution/1°C accuracy on remote channels 1°C resolution/1°C accuracy on local channel Extended, switchable temperature measurement range 0°C to 127°C (default) or –64°C to +191°C 2-wire SMBus serial interface with SMBus alert ...
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... Typical Performance Characteristics..............................................7 Theory of Operation.........................................................................9 Temperature Measurement Method...........................................9 Temperature Measurement Results ..........................................10 Temperature Measurement Range............................................10 Temperature Data Format..........................................................10 REVISION HISTORY 02/08—Rev 1: Conversion to ON Semiconductor 07/05—Revision 0: Initial Version Registers .......................................................................................11 Serial Bus Interface .....................................................................17 Addressing the Device................................................................17 ALERT Output ............................................................................19 Masking the ALERT Output .....................................................19 Low Power Standby Mode ...
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SPECIFICATIONS T = −40°C to +125° 3.6 V, unless otherwise noted Table 1. Parameter POWER SUPPLY Supply Voltage Average Operating Supply Current Undervoltage Lockout Threshold Power-On-Reset Threshold 2 TEMPERATURE-TO-DIGITAL ...
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ADT7483A SMBUS TIMING SPECIFICATIONS Table 2. 1 Parameter Limit MIN MAX f 400 SCLK t 4.7 LOW t 4 HIGH 300 F t 4.7 SU; STA HD; STA 3 ...
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ABSOLUTE MAXIMUM RATINGS Table 3. Parameter Positive Supply Voltage ( GND DD D+ D− to GND SCLK, SDATA, ALERT , THERM Input Current, SDATA, THERM Input Current, D− ESD Rating, All Pins (Human Body Model) Maximum Junction Temperature ...
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ADT7483A PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 4. Pin Function Descriptions Pin No. Mnemonic Description 1 ADD1 Address 1 Pin. Tri-state input to set the SMBus address Positive Supply 3 D1+ Positive ...
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TYPICAL PERFORMANCE CHARACTERISTICS 3.5 DEV 1 DEV 8 DEV 15 3.0 DEV 2 DEV 9 DEV 16 DEV 3 DEV 10 MEAN DEV 4 DEV 11 HIGH 4Σ 2.5 DEV 5 DEV 12 LOW 4Σ DEV 6 DEV 13 2.0 ...
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ADT7483A 422 420 418 416 414 DEV 3BC DEV 4BC 412 410 408 3.0 3.1 3.2 3.3 V (V) DD Figure 10. Operating Supply Current vs. Voltage 4.4 4.2 4.0 3.8 3.6 3.4 3.2 3.0 3.0 3.1 3.2 3.3 V ...
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THEORY OF OPERATION The ADT7483A is a local and 2x remote temperature sensor and over/under temperature alarm. When the ADT7483A is operating normally, the on-board ADC operates in a free- running mode. The analog input multiplexer alternately selects either the ...
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ADT7483A TEMPERATURE MEASUREMENT RESULTS The results of the local and remote temperature measurements are stored in the local and remote temperature value registers and are compared with limits programmed into the local and remote high and low limit registers. The ...
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Table 7. Temperature Data Format (Local and Remote Temperature High Byte) Temperature –55°C 0°C +1°C +10°C +25°C +50°C +75°C +100°C +125°C +127°C +150°C 1 Offset binary scale temperature values are offset by +64. 2 Binary scale temperature measurement returns 0 ...
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ADT7483A Configuration 1 Register Table 8. Configuration 1 Register (Read Address = 0x03, Write Address = 0x09) Bit Mnemonic Function 7 Mask Setting this bit to 1 masks all ALERT s on the ALERT pin. Default = 0 = ALERT ...
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Table 10. Conversion Rate/Channel Selector Register Bit Mnemonic Function 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 rates, hence, setting this bit ...
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ADT7483A Status Registers The status registers are read-only registers, at Address 0x02 (Status Register 1) and Address 0x23 (Status Register 2). They contain status information for the ADT7483A. Table 11. Status Register 1 Bit Assignments Bit Mnemonic Function 7 BUSY ...
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The value in the offset register is added or subtracted to the measured value of the remote temperature. The offset register powers up with a default value of 0°C and will have no effect unless the user writes a different ...
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ADT7483A Table 15. List of ADT7483A Registers Read Write Address Address (Hex) (Hex) Mnemonic N/A N/A Address Pointer 00 N/A Local Temperature Value 01 N/A Remote 1 Temperature Value High Byte 01 N/A Remote 2 Temperature Value High Byte 02 ...
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SERIAL BUS INTERFACE Control of the ADT7483A is carried out via the serial bus. The ADT7483A is connected to the serial bus as a slave device, under the control of a master device. The ADT7483A has an SMBus timeout feature. ...
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ADT7483A write operation contains a second data byte that is written to the register selected by the address pointer register (see Figure 16). The device address is sent over the bus followed by R/W set to 0. This is followed ...
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Notes • possible to read a data byte from a data register without first writing to the address pointer register. However, if the address pointer register is already at the correct value not possible to write ...
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ADT7483A registers are now outside the new limits, an ALERT is generated, even though the ADT7483A is still in standby. SENSOR FAULT DETECTION The ADT7483A has internal sensor fault detection circuitry located at its D+ input. This circuit can detect ...
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If the measured temperature exceeds the high temperature limit, the ALERT output asserts low. • If the temperature continues to increase and exceeds the THERM limit, the THERM output asserts low. This can be used to throttle the CPU ...
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ADT7483A APPLICATIONS NOISE FILTERING For temperature sensors operating in noisy environments, previous practice was to place a capacitor across the D+ and D− pins to help combat the effects of noise. However, large capacitances affect the accuracy of the temperature ...
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LAYOUT CONSIDERATIONS Digital boards can be electrically noisy environments, and the ADT7483A measures very small voltages from the remote sensor, so care must be taken to minimize noise induced at the sensor inputs. Follow these precautions: • Place the ADT7483A ...
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... ADT7483AARQZ −40°C to +125°C 1 ADT7483AARQZ-RL −40°C to +125°C 1 ADT7483AARQZ-R7 −40°C to +125°C EVAL-ADT7483EB −40°C to +125° Pb-free part. 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. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. “ ...