Document
±2°C Accurate, Micropower Digital Temperature Sensor
ADT7302
FEATURES
13-bit temperature-to-digital converter −40°C to +125°C operating temperature range ±2°C accuracy 0.03125°C temperature resolution Shutdown current of 1 μA Power dissipation of 0.631 mW at VDD = 3.3 V SPI- and DSP-compatible serial interface Shutdown mode Space-saving SOT-23 and MSOP packages Compatible with AD7814
APPLICATIONS
Medical equipment Automotive
Environmental controls Oil temperature Hydraulic systems Cell phones Hard disk drives Personal computers Electronic test equipment Office equipment Domestic appliances Process control
GENERAL DESCRIPTION
The ADT7302 is a complete temperature monitoring system available in SOT-23 and MSOP packages. It contains a band gap temperature sensor and a 13-bit ADC to monitor and digitize the temperature reading to a resolution of 0.03125°C.
The ADT7302 has a flexible serial interface that allows easy interfacing to most microcontrollers. The interface is compatible with SPI®, QSPI™, and MICROWIRE™ protocols as well as DSPs. The part features a standby mode that is controlled via the serial interface.
The ADT7302’s wide supply voltage range, low supply current, and SPI-compatible interface make it ideal for a variety of applications, including PCs, office equipment, automotive, and domestic appliances.
FUNCTIONAL BLOCK DIAGRAM
GND
BAND GAP TEMPERATURE
SENSOR
ADT7302
13-BIT ANALOG/DIGITAL
CONVERTER
TEMPERATURE VALUE
REGISTER
SERIAL BUS
INTERFACE
Figure 1.
VDD
CS SCLK DIN DOUT
04662-001
PRODUCT HIGHLIGHTS
1. On-chip temperature sensor that allows an accurate measurement of the ambient temperature. The measurable temperature range is −40°C to +125°C.
2. Supply voltage of 2.7 V to 5.25 V.
3. Space-saving 6-lead SOT-23 and 8-lead MSOP packages.
4. Maximum temperature accuracy of ±2°C.
5. 13-bit temperature reading to 0.03125°C resolution.
6. Shutdown mode that reduces the power consumption to 4.88 μW with VDD = 3.3 V at 1 SPS.
7. Compatible with AD7814.
Rev. B
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ADT7302
TABLE OF CONTENTS
Features .............................................................................................. 1 Applications....................................................................................... 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Product Highlights ........................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3
Timing Characteristics ................................................................ 4 Absolute Maximum Ratings............................................................ 5
ESD Caution.................................................................................. 5 Pin Configurations and Function Descriptions ........................... 6
REVISION HISTORY
6/11—Rev. A to Rev. B Changed Temperature Conversion Time from 800 µs to 1.2 ms.. 3 Changed Temperature Conversion Time in Converter Details Section .................................................................................. 9 3/10—Rev. 0 to Rev. A Change to Autoconversion Update Rate Parameter, Table 1 ...... 3 Changes to Converter Details Section ........................................... 9 Updated Outline Dimensions ....................................................... 15
10/05—Revision 0: Initial Version
Typical Performance Characteristics ..............................................7 Theory of Operation .........................................................................9
Converter Details ..........................................................................9 Temperature Value Register.........................................................9 Serial Interface ............................................................................ 10 Applications Information .............................................................. 12 Microprocessor Interfacing....................................................... 12 Mounting the ADT7302.............................................