Automotive, 1C Accurate, 16-Bit, 175C, Digital SPI Temperature Sensor in Die Form Data Sheet ADT7312 FEATURES GENERAL DESCRIPTION Qualified for automotive applications The ADT7312 is a 1C accurate digital temperature sensor High performance that operates over a very wide temperature range of 55C to Temperature accuracy: +175C and is available in die form only. It contains an internal 1C from 55C to +175C (2.7 V to 3.3 V) band gap reference, a temperature sensor, and a 16-bit analog- 16-bit temperature resolution: 0.0078C to-digital converter (ADC) to monitor and digitize the temper- Fast first temperature conversion on power-up of 6 ms ature to a resolution of 0.0078C. The default ADC resolution Easy implementation is 13 bits (0.0625C). The ADC resolution can be changed to No temperature calibration or correction required 16 bits (0.0078C) using the serial interface. No linearity correction required The ADT7312 is guaranteed to operate over supply voltages Low power from 2.7 V to 5.5 V. At 3.6 V operation, the average supply Power-saving 1 sample per second (SPS) mode current is typically 245 A. The ADT7312 has a shutdown 880 W typical at 3.6 V in normal mode mode that powers down the device, resulting in a typical 9 W typical at 3.6 V in shutdown mode shutdown current of 2.5 A at 3.6 V. The ADT7312 is rated Wide operating ranges for operation over the 55C to +175C temperature range. Temperature range: 55C to +175C The CT pin is an open-drain output that becomes active when Voltage range: 2.7 V to 5.5 V the temperature exceeds a programmable critical temperature Programmable interrupts limit. The default critical temperature limit is 147C. The INT Critical overtemperature interrupt pin is also an open-drain output that becomes active when the Overtemperature/undertemperature interrupt temperature exceeds a programmable limit. The INT pin and SPI-compatible interface the CT pin can operate in either comparator or interrupt mode. Available in die form only PRODUCT HIGHLIGHTS APPLICATIONS 1. Ease of use, no calibration or correction required. Automotive 2. Low power consumption. High temperature monitoring 3. Excellent long-term stability and reliability. High temperature thermal protection 4. Qualified for automotive applications. FUNCTIONAL BLOCK DIAGRAM ADT7312 INTERNAL INTERNAL REFERENCE OSCILLATOR SCLK 1 6 CT T CRIT DOUT 2 - TEMPERATURE MODULATOR SENSOR INT 5 DIN 3 T HIGH CS 4 FILTER 7 GND LOGIC T LOW 8 GND CONFIGURATION T T STATUS CRIT LOW REGISTER REGISTER REGISTER REGISTER 9 V DD 10 V DD TEMPERATURE T T ID HYST HIGH VALUE REGISTER REGISTER REGISTER REGISTER Figure 1. Rev. A 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 www.analog.com license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Fax: 781.461.3113 2012 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. SPI INTERFACE 06791-001ADT7312 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Temperature Value Register ...................................................... 15 Applications ....................................................................................... 1 ID Register................................................................................... 15 General Description ......................................................................... 1 TCRIT Setpoint Register ............................................................... 15 Product Highlights ........................................................................... 1 THYST Setpoint Register ............................................................... 16 Functional Block Diagram .............................................................. 1 THIGH Setpoint Register .............................................................. 16 Revision History ............................................................................... 2 T Setpoint Register ............................................................... 16 LOW Specif icat ions ..................................................................................... 3 Serial Interface ................................................................................ 17 SPI Timing Specifications ........................................................... 4 SPI Command Byte .................................................................... 17 Absolute Maximum Ratings ............................................................ 5 Writing Data ............................................................................... 18 ESD Caution .................................................................................. 5 Reading Data ............................................................................... 19 Pad Configuration and Function Descriptions ............................ 6 Interfacing to DSPs or Microcontrollers ................................. 19 Die Bond Pad Coordinates .............................................................. 7 Resetting the Serial Interface .................................................... 19 Typical Performance Characteristics ............................................. 8 INT and CT Outputs ...................................................................... 20 Theory of Operation ........................................................................ 9 Undertemperature and Overtemperature Detection ............ 20 Circuit Description....................................................................... 9 Redundant Critical Generator .................................................. 21 Converter Architecture ................................................................ 9 Applications Information .............................................................. 22 Normal Mode (Continuous Conversion Mode) ...................... 9 Thermal Response Time ........................................................... 22 One-Shot Mode .......................................................................... 10 Supply Decoupling ..................................................................... 22 1 SPS Mode .................................................................................. 11 Powering from a Switching Regulator ..................................... 22 Shutdown Mode .......................................................................... 11 Temperature Monitoring ........................................................... 22 Fault Queue ................................................................................. 11 Quick Guide to Measuring Temperature ................................ 22 Temperature Data Format ......................................................... 12 Outline Dimensions ....................................................................... 23 Temperature Conversion Formulas ......................................... 12 Ordering Guide .......................................................................... 23 Registers ........................................................................................... 13 Automotive Products ................................................................. 23 Status Register ............................................................................. 13 Configuration Register .............................................................. 14 REVISION HISTORY 6/12Rev. 0 to Rev. A Changed High Output Leakage Current, IOH Maximum Parameter from 5 A to 1 A ....................................................... 3 1/12Revision 0: Initial Version Rev. A Page 2 of 24