0.25C Accurate, 16-Bit Digital 2 I C Temperature Sensor Data Sheet ADT7420 FEATURES GENERAL DESCRIPTION High performance The ADT7420 is a high accuracy digital temperature sensor Temperature accuracy offering breakthrough performance over a wide industrial 0.20C from 10C to +85C at 3.0 V range, housed in a 4 mm 4 mm LFCSP package. It contains an 0.25C from 20C to +105C from 2.7 V to 3.3 V internal band gap reference, a temperature sensor, and a 16-bit 16-bit resolution: 0.0078C ADC to monitor and digitize the temperature to 0.0078C Ultralow temperature drift: 0.0073C resolution. The ADC resolution, by default, is set to 13 bits NIST traceable or equivalent (0.0625C). The ADC resolution is a user programmable mode Fast first temperature conversion on power-up of 6 ms that can be changed through the serial interface. Easy implementation The ADT7420 is guaranteed to operate over supply voltages from No temperature calibration/correction required by user 2.7 V to 5.5 V. Operating at 3.3 V, the average supply current is typi- No linearity correction required cally 210 A. The ADT7420 has a shutdown mode that powers Low power down the device and offers a shutdown current of typically 2.0 A Power-saving 1 sample per second (SPS) mode at 3.3 V. The ADT7420 is rated for operation over the 40C to 700 W typical at 3.3 V in normal mode +150C temperature range. 7 W typical at 3.3 V in shutdown mode Wide operating ranges Pin A0 and Pin A1 are available for address selection, giving the 2 Temperature range: 40C to +150C ADT7420 four possible I C addresses. The CT pin is an open- Voltage range: 2.7 V to 5.5 V drain output that becomes active when the temperature exceeds Programmable interrupts a programmable critical temperature limit. The INT pin is also Critical overtemperature interrupt an open-drain output that becomes active when the tempera- Overtemperature/undertemperature interrupt ture exceeds a programmable limit. The INT pin and CT pin 2 I C-compatible interface can operate in comparator and interrupt event modes. 16-lead, 4 mm 4 mm LFCSP RoHS-compliant package PRODUCT HIGHLIGHTS APPLICATIONS 1. Ease of use, no calibration or correction required by the user. RTD and thermistor replacement 2. Low power consumption. Thermocouple cold junction compensation 3. Excellent long-term stability and reliability. Medical equipment 4. High accuracy for industrial, instrumentation, and medical Industrial control and test applications. Food transportation and storage 5. Packaged in a 16-lead, 4 mm 4 mm LFCSP RoHS- Environmental monitoring and HVAC compliant package. Laser diode temperature control FUNCTIONAL BLOCK DIAGRAM V 12 DD CONFIGURATION TEMPERATURE 10 CT INTERNAL REGISTER VALUE REGISTER OSCILLATOR T CRIT INTERNAL T T LOW CRIT REFERENCE REGISTER REGISTER 9 INT - T T TEMPERATURE HYST HIGH T MODULATOR HIGH REGISTER REGISTER SENSOR ID STATUS REGISTER REGISTER ADT7420 FILTER T LOW SOFTWARE POINTER LOGIC RESET REGISTER REGISTER A0 3 1 SCL 2 I C INTERFACE 4 2 SDA A1 11 GND Figure 1. Rev. A Document Feedback Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. rights of third parties that may result from its use. Specifications subject to change without notice. No Tel: 781.329.4700 20122017 Analog Devices, Inc. All rights reserved. license is granted by implication or otherwise under any patent or patent rights of Analog Devices. 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Technical Support www.analog.com 09013-001ADT7420 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Temperature Value Registers .................................................... 13 Applications ....................................................................................... 1 Status Register ............................................................................. 14 General Description ......................................................................... 1 Configuration Register .............................................................. 14 Product Highlights ........................................................................... 1 THIGH Setpoint Registers ............................................................. 15 Functional Block Diagram .............................................................. 1 T Setpoint Registers .............................................................. 15 LOW Revision History ............................................................................... 2 T Setpoint Registers .............................................................. 15 CRIT Specifications ..................................................................................... 3 T Setpoint Register ............................................................... 16 HYST 2 I C Timing Specifications ............................................................ 5 ID Register................................................................................... 16 Absolute Maximum Ratings ............................................................ 6 Serial Interface ................................................................................ 17 ESD Caution .................................................................................. 6 Serial Bus Address ...................................................................... 17 Pin Configuration and Function Descriptions ............................. 7 Writing Data ............................................................................... 18 Typical Performance Characteristics ............................................. 8 Reading Data ............................................................................... 19 Theory of Operation ...................................................................... 10 Reset ............................................................................................. 20 Circuit Information .................................................................... 10 General Call ................................................................................ 20 Converter Details........................................................................ 10 INT and CT Outputs ...................................................................... 21 Normal Mode .............................................................................. 10 Undertemperature and Overtemperature Detection ............ 21 One-Shot Mode .......................................................................... 10 Applications Information .............................................................. 23 1 SPS Mode .................................................................................. 11 Thermal Response Time ........................................................... 23 Shutdown ..................................................................................... 11 Supply Decoupling ..................................................................... 23 Fault Queue ................................................................................. 11 Powering from a Switching Regulator ..................................... 23 Temperature Data Format ......................................................... 12 Temperature Measurement ....................................................... 23 Temperature Conversion Formulas ......................................... 12 Quick Guide to Measuring Temperature ................................ 23 Registers ........................................................................................... 13 Outline Dimensions ....................................................................... 24 Address Pointer Register ........................................................... 13 Ordering Guide .......................................................................... 24 REVISION HISTORY 9/2017Rev. 0 to Rev. A 12/2012Revision 0: Initial Version Changes to Figure 3 .......................................................................... 7 Added 0x0C Register Address, 0x0D Register Address, and 0x2E Register Address, Table 6 ..................................................... 13 Updated Outline Dimensions ....................................................... 24 Changes to Ordering Guide .......................................................... 24 Rev. A Page 2 of 24