AD7765 Analog Devices, AD7765 Datasheet - Page 2

• Manufacturer Part Number: AD7765
• Description: 24-Bit, 156 kSPS, 112 dB Sigma-Delta ADC with On-Chip Buffers and Serial Interface
• Manufacturer: Analog Devices

Specifications of AD7765

• Resolution (bits): 24bit
• # Chan: 1
• Sample Rate: 40MSPS
• Interface: Ser,SPI
• Analog Input Type: Diff-Uni
• Ain Range: 6.5 V p-p
• Adc Architecture: Sigma-Delta
• Pkg Type: SOP

AD7765
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications ....................................................................................... 1
General Description ......................................................................... 1
Functional Block Diagram .............................................................. 1
Revision History ............................................................................... 2
Specifications ..................................................................................... 3
Absolute Maximum Ratings ............................................................ 8
Pin Configuration and Function Descriptions ............................. 9
Typical Performance Characteristics ........................................... 11
Terminology .................................................................................... 14
Theory of Operation ...................................................................... 15
AD7765 Input Structure ................................................................ 17
AD7765 Interface ............................................................................ 20
REVISION HISTORY
8/09—Rev. 0 to Rev. A
Changes to Table 3 ............................................................................ 6
Changes to Table 4 ............................................................................ 8
Changes to Σ-Δ Modulation and Digital Filtering Section ....... 15
Added AD7765 Antialias Protection Section ............................. 16
Added Driving the Modulator Inputs Directly Section ............ 19
Changes to Synchronization Section, Added Figure 35 ............ 21
Changes to Power Modes Section, Added RESET /
Mode Section, Added Figure 38 ................................................... 22
Changes to Daisy Chaining Section ............................................. 23
Changes to Using the AD7765 Section ........................................ 27
6/07—Revision 0: Initial Version
Timing Specifications .................................................................. 6
Timing Diagrams .......................................................................... 7
ESD Caution .................................................................................. 8
Σ-Δ Modulation and Digital Filtering ...................................... 15
AD7765 Antialias Protection .................................................... 16
On-Chip Differential Amplifier ............................................... 18
Modulator Input Structure ........................................................ 19
Driving the Modulator Inputs Directly ................................... 19
Reading Data ............................................................................... 20
Reading Status and Other Registers ......................................... 20
Writing to the AD7765 .............................................................. 20
PWRDWN
Rev. A | Page 2 of 32
AD7765 Functionality ................................................................... 21
Daisy Chaining ............................................................................... 23
Clocking the AD7765 .................................................................... 25
Decoupling and Layout Information ........................................... 26
AD7765 Registers ........................................................................... 28
Outline Dimensions ....................................................................... 30
Synchronization .......................................................................... 21
Overrange Alerts ........................................................................ 21
Power Modes ............................................................................... 22
Decimation Rate Pin .................................................................. 22
Reading Data in Daisy-Chain Mode ....................................... 23
Writing Data in Daisy-Chain Mode ........................................ 24
MCLK Jitter Requirements ....................................................... 25
Supply Decoupling ..................................................................... 26
Reference Voltage Filtering ....................................................... 26
Differential Amplifier Components ........................................ 26
Layout Considerations ............................................................... 26
Using the AD7765 ...................................................................... 27
Bias Resistor Selection ............................................................... 27
Control Register ......................................................................... 28
Status Register ............................................................................. 28
Gain Register—Address 0x0004 ............................................... 29
Overrange Register—Address 0x0005 ..................................... 29
Ordering Guide .......................................................................... 30