AD7794 Analog Devices, AD7794 Datasheet - Page 2

• Manufacturer Part Number: AD7794
• Description: 6-Channel, Low Noise, Low Power, 24-Bit Sigma Delta ADC with On-Chip In-Amp and Reference
• Manufacturer: Analog Devices

Specifications of AD7794

• Resolution (bits): 24bit
• # Chan: 6
• Sample Rate: n/a
• Interface: Ser,SPI
• Analog Input Type: Diff-Uni
• Ain Range: (2Vref/PGA Gain) p-p
• Adc Architecture: Sigma-Delta
• Pkg Type: SOP

AD7794/AD7795
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications....................................................................................... 1
General Description ......................................................................... 1
Functional Block Diagram .............................................................. 1
Revision History ............................................................................... 2
Specifications..................................................................................... 3
Timing Characteristics..................................................................... 8
Timing Diagrams.............................................................................. 9
Absolute Maximum Ratings.......................................................... 10
Pin Configuration and Function Descriptions........................... 11
RMS Noise and Resolution Specifications .................................. 13
Typical Performance Characteristics ........................................... 16
On-Chip Registers .......................................................................... 17
REVISION HISTORY
3/07—Rev. C to Rev. D
Changes to Specifications Endnote 1............................................. 7
Changes to Status Register Section .............................................. 18
Changes to Ordering Guide .......................................................... 36
10/06—Rev. B to Rev. C
Updated Format..................................................................Universal
Added AD7794 C-Grade Part...........................................Universal
Changes to Specifications ................................................................ 3
Changes to Ordering Guide .......................................................... 36
6/06—Rev. A to Rev. B
Added AD7795 ...................................................................Universal
Changes to Features.......................................................................... 1
Changes to Table 1............................................................................ 3
Changes to RMS Noise and Resolution
Specifications Section..................................................................... 12
Changes to Table 19........................................................................ 20
Changes to ADC Circuit Information Section ........................... 25
Changes to Ordering Guide .......................................................... 35
ESD Caution................................................................................ 10
Chop Enabled.............................................................................. 13
Chop Disabled ............................................................................ 15
Communications Register......................................................... 17
Status Register ............................................................................. 18
Mode Register ............................................................................. 19
Configuration Register .............................................................. 22
Data Register ............................................................................... 24
ID Register................................................................................... 24
IO Register................................................................................... 24
Offset Register............................................................................. 25
Rev. D | Page 2 of 36
ADC Circuit Information.............................................................. 26
Circuit Description......................................................................... 31
Applications Information .............................................................. 35
Outline Dimensions ....................................................................... 36
4/05—Rev. 0 to Rev. A
Changes to Absolute Maximum Ratings........................................9
Changes to Figure 21...................................................................... 25
Changes to Data Output Coding Section.................................... 28
Changes to Calibration Section .................................................... 30
Changes to Ordering Guide .......................................................... 33
10/04—Revision 0: Initial Version
Full-Scale Register...................................................................... 25
Overview ..................................................................................... 26
Digital Interface.......................................................................... 28
Analog Input Channel ............................................................... 31
Instrumentation Amplifier........................................................ 31
Bipolar/Unipolar Configuration .............................................. 31
Data Output Coding .................................................................. 32
Burnout Currents ....................................................................... 32
Excitation Currents .................................................................... 32
Bias Voltage Generator .............................................................. 32
Reference ..................................................................................... 32
Reference Detect......................................................................... 33
Reset ............................................................................................. 33
AV
Calibration................................................................................... 33
Grounding and Layout .............................................................. 34
Flowmeter.................................................................................... 35
Ordering Guide .......................................................................... 36
DD
Monitor ............................................................................. 33