Datasheet

AD7656-1/AD7657-1/AD7658-1 Data Sheet
Rev. D | Page 2 of 32
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications ....................................................................................... 1
Functional Block Diagram .............................................................. 1
General Description ......................................................................... 1
Product Highlights ........................................................................... 1
Revision History ............................................................................... 2
Specifications ..................................................................................... 3
AD7656-1 ...................................................................................... 3
AD7657-1 ...................................................................................... 5
AD7658-1 ...................................................................................... 7
Timing Specifications .................................................................. 9
Absolute Maximum Ratings .......................................................... 10
Thermal Resistance .................................................................... 10
ESD Caution ................................................................................ 10
Pin Configuration and Function Descriptions ........................... 11
Typical Performance Characteristics ........................................... 14
Terminology .................................................................................... 18
Theory of Operation ...................................................................... 20
Converter Details ....................................................................... 20
ADC Transfer Function ............................................................. 21
Internal/External Reference ...................................................... 21
Typical Connection Diagram ................................................... 21
Driving the Analog Inputs ........................................................ 22
Interface Options ........................................................................ 22
Software Selection of ADCs ...................................................... 24
Changing the Analog Input Range (
H
/S SEL = 0) ................ 25
Changing the Analog Input Range (
H
/S SEL = 1) ................ 25
Serial Read Operation ................................................................ 25
Daisy-Chain Mode (DCEN = 1, SER/
PAR
SEL = 1) ............. 27
Application Hints ........................................................................... 29
Layout .......................................................................................... 29
Power Supply Configuration..................................................... 29
Outline Dimensions ....................................................................... 30
Ordering Guide .......................................................................... 30
REVISION HISTORY
3/12—Rev. C to Rev. D
Changes to Figure 28 ...................................................................... 22
11/10—Rev. B to Rev. C
Added Power Supply Configuration Section .............................. 29
Added Figure 39 .............................................................................. 29
6/10—Rev. A to Rev. B
Changes to DC Accuracy Parameter, Table 1 ............................... 3
Changes to DC Accuracy Parameter, Table 2 ............................... 5
Change to DC Accuracy Parameter, Table 3 ................................. 7
Added %FSR to Terminology Section ......................................... 19
3/09—Rev. 0 to Rev. A
Changes to Features .......................................................................... 1
Changes to Table 1 ............................................................................ 3
Changes to Table 2 ............................................................................ 5
Changes to Table 3 ............................................................................. 7
Changes to Table 4 ............................................................................. 9
Changes to Absolute Maximum Ratings Table .......................... 10
Changes to Pin Functions Description Table ............................. 11
Changes to Figure 9 ........................................................................ 14
Changes to Converter Details Section ......................................... 20
Changes to Internal/External Reference Section ....................... 21
Changes to Interface Options Section ......................................... 22
Changes to Parallel Interface Section .......................................... 22
Changes to Serial Interface (SER/
PAR
SEL = 1) Section .......... 25
Changes to Daisy-Chain Mode (DCEN = 1, SER/
PAR
SEL = 1) .. 27
Changes to Layout Section ............................................................ 30
Updated Outline Dimension ........................................................ 31
Changes to Ordering Guide .......................................................... 31
7/08—Revision 0: Initial Version