Data SheetAD7949REVISION HISTORY 6/2017—Rev. E to Rev. F Changes to Figure 25 and Figure 26 ... 15 Changes to Table 9 .. 24 Changes to Bipolar Single Supply Section, Input Structure Updated Outline Dimensions .. 32 Section, and Selectable Low-Pass Filter Section ... 16 Changes to Ordering Guide ... 32 Changes to Input Configurations Section, Sequencer Section, and Source Resistance Section .. 17 5/2015—Rev. D to Rev. E Changes to Internal Reference/Temperature Sensor Section .. 18 Changed ADA4841-x to ADA4841-1, ADR43x to ADR430/ Added Figure 30; Renumbered Sequentially ... 18 ADR431/ADR433/ADR434/ADR435, and AD44x to ADR440/ Changes to External Reference and Internal Buffer Section, ADR441/ADR443/ADR444/ADR445 .. Throughout External Reference Section, and Reference Decoupling Updated Outline Dimensions .. 32 Section .. 19 Changes to Ordering Guide ... 32 Added Figure 31 and Figure 32 ... 19 Changes to Power Supply Section ... 20 3/2012—Rev. C to Rev. D Changed Reading/Writing During Conversion, Fast Hosts Changes to Figure 26 .. 16 Section to Reading/Writing After Conversion, Changes to Internal Reference/Temperature Sensor Section .. 19 Any Speed Hosts ... 21 Changes to External Reference and Internal Buffer Section ... 20 Changes to Configuration Register, CFG Section and Changes to Bits[5:3] Function, Table 9 ... 24 Table 9 ... 22 Updated Outline Dimensions .. 32 Added General Timing Without a Busy Indicator Section and Figure 36 ... 23 8/2011—Rev. B to Rev. C Added General Timing with a Busy Indicator Section and Changes to Internal Reference Section .. 18 Figure 37 ... 24 Changes to External Reference and Internal Buffer Section and Added Channel Sequencer Section, Examples Section, and External Reference Section .. 19 Figure 38 ... 25 Changes to Bits[5:3] Function, Table 9 ... 22 Changes to Read/Write Spanning Conversion Without a Busy Indicator Section and Figure 40 .. 26 5/2009—Rev. A to Rev. B Changes to Read/Write Spanning Conversion with a Busy Changes to Features Section, Applications Section, and Indicator Section and Figure 42 .. 27 Figure 1 ... 1 Changes to Evaluating AD7949 Performance Section ... 28 Changes to Specifications Section ... 3 Added Exposed Pad Notation to Outline Dimensions .. 29 Changes to Timing Specifications Section ... 5 Changes to Ordering Guide ... 29 Changes to Table 5 .. 7 Changes to Figure 4 and Table 6 ... 8 5/2008—Rev. 0 to Rev. A Changes to Figure 20 .. 11 Changes to Ordering Guide ... 26 Changes to Converter Operation Section .. 13 Changes to Table 7 .. 14 5/2008—Revision 0: Initial Version Rev. F | Page 3 of 32 Document Outline FEATURES APPLICATIONS FUNCTIONAL BLOCK DIAGRAM GENERAL DESCRIPTION REVISION HISTORY SPECIFICATIONS TIMING SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS TERMINOLOGY THEORY OF OPERATION OVERVIEW CONVERTER OPERATION TRANSFER FUNCTIONS TYPICAL CONNECTION DIAGRAMS Unipolar or Bipolar Bipolar Single Supply ANALOG INPUTS Input Structure Selectable Low-Pass Filter Input Configurations Sequencer Source Resistance DRIVER AMPLIFIER CHOICE VOLTAGE REFERENCE OUTPUT/INPUT Internal Reference/Temperature Sensor External Reference and Internal Buffer External Reference Reference Decoupling POWER SUPPLY SUPPLYING THE ADC FROM THE REFERENCE DIGITAL INTERFACE READING/WRITING DURING CONVERSION, FAST HOSTS READING/WRITING AFTER CONVERSION, ANY SPEED HOSTS READING/WRITING SPANNING CONVERSION, ANY SPEED HOST CONFIGURATION REGISTER, CFG GENERAL TIMING WITHOUT A BUSY INDICATOR GENERAL TIMING WITH A BUSY INDICATOR CHANNEL SEQUENCER Examples READ/WRITE SPANNING CONVERSION WITHOUT A BUSY INDICATOR READ/WRITE SPANNING CONVERSION WITH A BUSY INDICATOR APPLICATION HINTS LAYOUT EVALUATING AD7949 PERFORMANCE OUTLINE DIMENSIONS ORDERING GUIDE