adt7420ucpz-rl7 Analog Devices, Inc., adt7420ucpz-rl7 Datasheet
adt7420ucpz-rl7
Related parts for adt7420ucpz-rl7
adt7420ucpz-rl7 Summary of contents
Page 1
... C INTERFACE 11 GND Figure 1. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 Fax: 781.461.3113 2 C Temperature Sensor ADT7420 2 C addresses. The CT pin is an open- ADT7420 CRIT INT 9 T HIGH T LOW 1 SCL 2 SDA www.analog.com ©2010 Analog Devices, Inc. All rights reserved. ...
Page 2
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 ...
Page 3
... Accuracy specification includes repeatability. 2 The equivalent 3-Σ limits are ±0.15°C. This 3-Σ specification is provided to enable comparison with other vendors who use these limits. 3 For higher accuracy operation, contact Analog Devices, Inc. 4 Based on a floating average of 10 readings. 5 Drift includes Solder Heat Resistance and life time test performed as per Jedec Standard JESD22-A108. ...
Page 4
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 ...
Page 5
Preliminary Technical Data ABSOLUTE MAXIMUM RATINGS Table 3. Parameter V to GND DD SDA Voltage to GND SCL Output Voltage to GND A0 Input Voltage to GND A1 Input Voltage to GND CT and INT Output Voltage to GND ESD ...
Page 6
ADT7420 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 4. Pin Function Descriptions Pin No. 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 ...
Page 7
Preliminary Technical Data TYPICAL PERFORMANCE CHARACTERISTICS 1.00 0.75 0.50 0.25 0 –0.25 –0.50 –0.75 –1.00 –50 –30 – TEMPERATURE (°C) Figure 4. Temperature Accuracy 1.00 0.75 0.50 0.25 0 –0.25 –0.50 –0.75 –1.00 –50 ...
Page 8
ADT7420 THEORY OF OPERATION CIRCUIT INFORMATION The ADT7420 is a 13-bit digital temperature sensor that is extend- able to 16 bits for greater resolution. An on-board temperature sensor generates a voltage proportional to absolute temperature, which is compared to an ...
Page 9
Preliminary Technical Data CT and INT Operation in One-Shot Mode See Figure 11 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 ...
Page 10
ADT7420 TEMPERATURE DATA FORMAT One LSB of the ADC corresponds to 0.0625°C in 13-bit mode or 0.0078°C in 16-bit mode. The ADC can theoretically measure a temperature range of 255°C, but the ADT7420 is guaranteed to measure a low value ...
Page 11
Preliminary Technical Data REGISTERS The ADT7420 contains 14 registers: • Nine temperature registers • A status register • register • A configuration register • An address pointer register • A software reset All registers are eight bits wide. ...
Page 12
ADT7420 STATUS REGISTER This 8-bit read-only register reflects the status of the overtempera- ture and undertemperature interrupts that can cause the CT and INT pins to go active. It also reflects the status of a temperature conversion operation. The interrupt ...
Page 13
Preliminary Technical Data T SETPOINT REGISTERS HIGH The T setpoint MSB and T setpoint LSB registers store HIGH HIGH the overtemperature limit value. An overtemperature event occurs when the temperature value stored in the temperature value register exceeds the value ...
Page 14
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. ...
Page 15
Preliminary Technical Data SERIAL INTERFACE TO INTERRUPT PIN ON MICROCONTROLLER Control of the ADT7420 is carried out via the I serial interface. The ADT7420 is connected to this bus as a slave and is under the control of a master ...
Page 16
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 ...
Page 17
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 ...
Page 18
ADT7420 RESET To reset the ADT7420 without having to reset the entire I an explicit reset command is provided. This uses a particular address pointer word as a command word to reset the part and upload all default settings. The ...
Page 19
Preliminary Technical Data INT AND CT OUTPUTS The INT and CT pins are open-drain outputs, and both pins require a 10 kΩ pull-up resistor UNDERTEMPERATURE AND OVERTEMPERATURE DETECTION The INT and CT pins have two undertemperature/overtemperature ...
Page 20
ADT7420 (COMPARATOR MODE) POLARITY = ACTIVE LOW (INTERRUPT MODE) POLARITY = ACTIVE LOW (COMPARATOR MODE) POLARITY = ACTIVE HIGH (INTERRUPT MODE) POLARITY = ACTIVE HIGH Figure 18. INT Output Temperature Response Diagram for T TEMPERATURE –13°C –14°C –15°C –16°C –17°C ...
Page 21
Preliminary Technical Data APPLICATIONS INFORMATION THERMAL RESPONSE TIME The time required for a temperature sensor to settle to a specified accuracy is a function of the thermal mass of the sensor and the thermal conductivity between the sensor and the ...
Page 22
... ADT7420 OUTLINE DIMENSIONS PIN 1 INDICATOR 0.80 0.75 0.70 SEATING PLANE ORDERING GUIDE 1 Model Operating Temperature Range ADT7420UCPZ-R2 −40°C to +150°C ADT7420UCPZ-RL7 −40°C to +150°C EVAL-ADT7X20EBZ RoHS Compliant Part. 4.10 0.35 4.00 SQ 0.30 3.90 0.25 13 0.65 12 BSC EXPOSED PAD 9 8 0.45 TOP VIEW BOTTOM VIEW 0.40 0.35 0.05 MAX 0.02 NOM COPLANARITY 0.08 0.20 REF COMPLIANT TO JEDEC STANDARDS MO-220-WGGC ...
Page 23
Preliminary Technical Data NOTES Rev. PrB | Page ADT7420 ...
Page 24
... ADT7420 NOTES refers to a communications protocol originally developed by Philips Semiconductors (now NXP Semiconductors). ©2010 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. PR09013-0-8/10(PrB) Preliminary Technical Data Rev. PrB | Page ...