ADT7420 Analog Devices, ADT7420 Datasheet
ADT7420
Related parts for ADT7420
ADT7420 Summary of contents
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... The ADT7420 has a shutdown mode that powers down the device and offers a shutdown current of typically 2 μA. The ADT7420 is rated for operation over the −40 ° +150°C temperature range. Pin A0 and Pin A1 are available for address selection, giving the ...
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... ADT7420 TABLE OF CONTENTS Features .............................................................................................. 1 Applications ....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Specifications ..................................................................................... Timing Specifications ............................................................ 4 Absolute Maximum Ratings ............................................................ 5 ESD Caution .................................................................................. 5 Pin Configuration and Function Descriptions ............................. 6 Typical Performance Characteristics ............................................. 7 Theory of Operation ........................................................................ 9 Circuit Information ...................................................................... 9 Converter Details.......................................................................... 9 Temperature Measurement ......................................................... 9 One-Shot Mode ............................................................................ 9 1 SPS Mode .................................................................................... 9 Shutdown ...
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... Rev. PrA | Page 3 of www.DataSheet4U.com ADT7420 Test Conditions/Comments T = −10°C to +85° 3 −20°C to +105° −40°C to +125° −10°C to +105° ...
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... ADT7420 TIMING SPECIFICATIONS T = −40°C to +150° 2 5.5 V, unless otherwise noted. All input signals are specified with rise time ( (10 and timed from a voltage level of 1 Table 2. Parameter 1, 2 SERIAL INTERFACE SCL Frequency SCL High Pulse Width, t ...
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... − )/θ MAX JMAX A JA 121°C/W 56°C/W 220°C 260°C (0°C) 20 sec to 40 sec 3°C/sec maximum −6°C/sec maximum 8 minutes maximum Rev. PrA | Page 5 of www.DataSheet4U.com ADT7420 ...
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... Mnemonic Description 2 1 SCL I C Serial Clock Input. The serial clock is used to clock in and clock out data to and from any register of the ADT7420. Open-drain configuration. A pull-up resistor is required, typically 10 kΩ. 2 SDA Serial Data Input/Output. Serial data to and from the part is provided on this pin. Open-drain configuration. A pull-up resistor is required, typically 10 kΩ ...
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... Rev. PrA | Page 7 of www.DataSheet4U.com 5.5V CONTINUOUS CONVERSION 3.0V CONTINUOUS CONVERSION 5.5V 1SPS 3.0V 1SPS 0 –100 – 100 TEMPERATURE (°C) Figure 6. Operating Supply Current vs. Temperature 5.5V 5.0V 5 4.5V 3.6V 0 –100 – 100 TEMPERATURE (°C) Figure 7. Shutdown Current vs. Temperature ADT7420 150 200 3.3V 3.0V 2.7V 150 200 ...
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... ADT7420 0.30 I CONTINUOUS CONVERSION DD 0.25 0.20 0.15 0.10 I 1SPS DD 0.05 0 2.5 3.0 3.5 4.0 4.5 SUPPLY VOLTAGE (V) Figure 8. Average Operating Supply Current vs. Supply Voltage at 25° 2.5 3.0 3.5 4.0 4.5 SUPPLY VOLTAGE (V) Figure 9. Shutdown Current vs. Supply Voltage at 25°C 160 140 120 100 5.0 5.5 6.0 5.0 5.5 6.0 Rev. PrA | Page 8 of www.DataSheet4U.com ...
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... Wait for a minimum of 240 ms after writing to the operation mode bits to the one-shot bits before reading back the temperature from the temperature value register. This time ensures that the ADT7420 has time to power up and complete a conversion. The one-shot mode is useful when one of the circuit design priorities is to reduce power consumption ...
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... ADT7420 CT and INT Operation in One-Shot Mode See Figure 12 for more information on one-shot CT pin operation for T overtemperature events when one of the CRIT limits is exceeded. Note that in interrupt mode, a read from any register resets the INT and CT pins. For the INT pin in the comparator mode, if the temperature drops below the T – ...
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... Preliminary Technical Data SHUTDOWN The ADT7420 can be placed in shutdown mode by writing 1 to Bit 5 and 1 to Bit 6 of the configuration register (Register Address 0x03), in which case the entire IC is shut down and no further conversions are initiated until the ADT7420 is taken out of shutdown mode. The ADT7420 can be taken out of shutdown mode by writing 0 to Bit 5 and 0 to Bit 6 in the configuration register (Register Address 0x03) ...
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... Reading back the temperature from the temperature value register requires a 2-byte read. Designers that use a 9-bit temperature data format can still use the ADT7420 by ignoring the last four LSBs of the 13-bit temperature value. These four LSBs are Bit 6 to Bit 3 in Table 5. ...
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... Temp ADDRESS POINTER REGISTER This register is always the first register written to during a write to the ADT7420. It should be set to the address of the register to which the write or read transaction is intended. Table 7 shows the register address of each register on the ADT7420. The default value of the address pointer register is 0x00. ...
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... These two bits set the operational mode for the ADT7420 continuous conversion (default). When one conversion is finished, the ADT7420 starts another one shot. Conversion time is typically 240 ms SPS mode. Conversion time is typically 60 ms. This operational mode reduces the average current consumption ...
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... LSBs of the critical overtemperature limit, stored in twos complement format. CRIT Rev. PrA | Page 15 of www.DataSheet4U.com setpoint LSB). LOW setpoint is 10°C. LOW setpoint MSB and T setpoint LSB registers store CRIT setpoint MSB) needs to be loaded CRIT setpoint LSB). CRIT limit is 147°C. CRIT ADT7420 ...
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... ADT7420 T SETPOINT REGISTER HYST This 8-bit read/write register stores the temperature hysteresis value for the and T temperature limits. The HIGH LOW CRIT temperature hysteresis value is stored in straight binary format using four LSBs. Increments are possible in steps of 1°C from 0°C to 15°C. The value in this register is subtracted from the ...
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... Like all I C-compatible devices, the ADT7420 has a 7-bit serial address. The five MSBs of this address for the ADT7420 are set to 10010. Pin A1 and Pin A0 set the two LSBs. These pins can be configured two ways, low and high, to give four different address options. Table 20 shows the different bus address options available. The recommended pull-up resistor value on the SDA and SCL lines is 10 kΩ ...
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... ADT7420 WRITING DATA It is possible to write either a single byte of data or two bytes to the ADT7420, depending on which registers are to be written. Writing a single byte of data requires the serial bus address, the data register address written to the address pointer register, followed by the data byte written to the selected data register. ...
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... Preliminary Technical Data READING DATA Reading data from the ADT7420 is done in a single data byte operation for the configuration register, the status register, the T register, and the ID register. A two data byte read HYST operation is needed for the temperature value register, T register, T ...
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... D1 R/W A0 ACK. BY TEMPERATURE ADT7420 VALUE REGISTER MSB DATA Figure 17. Reading Back Data from the Temperature Value Register Rev. PrA | Page www.DataSheet4U.com Preliminary Technical Data ACK. BY ADT7420 ACK. BY TEMPERATURE MASTER VALUE REGISTER LSB DATA 9 NO ACK. BY MASTER ...
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... Putting the ADT7420 into shutdown mode does not reset the INT state in comparator mode. Interrupt Mode In interrupt mode, the INT pin goes inactive when any ADT7420 register is read. Once the INT pin is reset, it goes active again only when the temperature is greater than the temperature stored ...
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... ADT7420 (COMPARATOR MODE) POLARITY = ACTIVE LOW (INTERRUPT MODE) POLARITY = ACTIVE LOW (COMPARATOR MODE) POLARITY = ACTIVE HIGH (INTERRUPT MODE) POLARITY = ACTIVE HIGH Figure 19. INT Output Temperature Response Diagram for T TEMPERATURE –13°C –14°C –15°C –16°C –17°C –18°C – ...
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... Of the pins on the ADT7420, the GND pin transfers most of the heat. Therefore, to measure the temperature of a heat source recommended that the thermal resistance between the GND pin of the ADT7420 and the GND of the heat source be reduced as much as possible. 0.1µF ADT7420 Rev ...
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... PLANE ORDERING GUIDE 1 Model Temperature Range ADT7420UCPZ −40°C to +150°C ADT7420UCPZ-R2 −40°C to +150°C ADT7420UCPZ-RL7 −40°C to +150°C EVAL-ADT7X20EBZ RoHS Compliant Part. 2 Maximum accuracy over the −20°C to +105°C temperature range refers to a communications protocol originally developed by Philips Semiconductors (now NXP Semiconductors). ...