AD7706 Analog Devices, AD7706 Datasheet - Page 2

• Manufacturer Part Number: AD7706
• Description: 3V/5V, 1mW, 3-Channel Pseudo Differential, 16-Bit Sigma-Delta ADC
• Manufacturer: Analog Devices

Specifications of AD7706

• Resolution (bits): 16bit
• # Chan: 3
• Sample Rate: n/a
• Interface: Ser,SPI
• Analog Input Type: Diff-Bip,Diff-Uni
• Ain Range: Bip (Vref)/(PGA Gain),Uni (Vref)/(PGA Gain)
• Adc Architecture: Sigma-Delta
• Pkg Type: DIP,SOIC,SOP

AD7705/AD7706
TABLE OF CONTENTS
Features .............................................................................................. 1
General Description ......................................................................... 1
Functional Block Diagram .............................................................. 1
Revision History ............................................................................... 3
Product Highlights ........................................................................... 4
Specifications..................................................................................... 5
Absolute Maximum Ratings............................................................ 9
Pin Configurations and Function Descriptions ......................... 10
Output Noise (5 V Operation)...................................................... 12
Output Noise (3 V Operation)...................................................... 13
Typical Performance Characteristics ........................................... 14
On-Chip Registers .......................................................................... 16
Circuit Description......................................................................... 21
Timing Characteristics ................................................................ 8
ESD Caution.................................................................................. 9
Communication Register (RS2, RS1, RS0 = 0, 0, 0)............... 16
Setup Register (RS2, RS1, RS0 = 0, 0, 1); Power-On/Reset
Status: 01 Hexadecimal .............................................................. 17
Clock Register (RS2, RS1, RS0 = 0, 1, 0); Power-On/Reset
Status: 05 Hexadecimal .............................................................. 19
Data Register (RS2, RS1, RS0 = 0, 1, 1) ................................... 20
Test Register (RS2, RS1, RS0 = 1, 0, 0); Power-On/Reset
Status: 00 Hexadecimal .............................................................. 20
Zero-Scale Calibration Register (RS2, RS1, RS0 = 1, 1, 0);
Power-On/Reset Status: 1F4000 Hexadecimal ........................... 20
Full-Scale Calibration Register (RS2, RS1, RS0 = 1, 1, 1);
Power-On/Reset Status: 5761AB HexaDecimal......................... 20
Analog Input ............................................................................... 22
Bipolar/Unipolar Input .............................................................. 22
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Theory of Operation ...................................................................... 28
Applications..................................................................................... 38
Outline Dimensions ....................................................................... 42
Reference Input........................................................................... 23
Digital Filtering........................................................................... 23
Analog Filtering.......................................................................... 25
Calibration................................................................................... 25
Clocking and Oscillator Circuit ............................................... 28
System Synchronization ............................................................ 28
RESET Input ............................................................................... 29
Standby Mode ............................................................................. 29
Accuracy ...................................................................................... 29
Drift Considerations .................................................................. 29
Power Supplies ............................................................................ 30
Supply Current............................................................................ 30
Grounding and Layout .............................................................. 30
Evaluating the Performance...................................................... 31
Digital Interface.......................................................................... 31
Configuring the AD7705/AD7706 .......................................... 33
Microcomputer/Microprocessor Interfacing ......................... 34
Code For Setting Up the AD7705/AD7706............................ 35
Pressure Measurement............................................................... 38
Temperature Measurement ....................................................... 39
Smart Transmitters..................................................................... 40
Battery Monitoring .................................................................... 41
Ordering Guide .......................................................................... 43