Data SheetAD9257PIN CONFIGURATION AND FUNCTION DESCRIPTIONSFFEEDDCC+–D–+DCSEAS+–D–+NNDNNDMEFNNDNNVIVIAVVIVIAVSYNVCVRSENRBIVIVIAVVIVI64636261605958575655545352515049PIN 1INDICATORAVDD148 AVDDVIN+ G247 VIN+ BVIN– G346 VIN– BAVDD445 AVDDVIN– H544 VIN– AVIN+ H643 VIN+ AAVDD7AD925742 AVDDAVDD841 PDWNTOP VIEWCLK–940 CSB(Not to Scale)CLK+ 1039 SDIO/DFSAVDD 1138 SCLK/DTPAVDD 1237 AVDDDNC 1336 DNCDRVDD 1435 DRVDDD– H 1534 D+ AD+ H 1633 D– A17181920212223242526272829303132–+GFFEOO–O+DDCCBBD– GD+D–D+D– ED+D–D+D–D+D–D+DCODCFCFCNOTES 05 0 1. DNC = DO NOT CONNECT. DO NOT CONNECT TO THIS PIN. 06- 2. THE EXPOSED PAD MUST BE CONNECTED TO ANALOG GROUND. 102 Figure 5. Pin Configuration, Top View Table 8. Pin Function Descriptions Pin No.MnemonicDescription 0, EP AGND, Exposed Pad Analog Ground, Exposed Pad. The exposed thermal pad on the bottom of the package provides the analog ground for the part. This exposed pad must be connected to ground for proper operation. 1, 4, 7, 8, 11, 12, 37, AVDD 1.8 V Analog Supply. 42, 45, 48, 51, 59, 62 13, 36 DNC Do Not Connect. 14, 35 DRVDD 1.8 V Digital Output Driver Supply. 2, 3 VIN+ G, VIN− G ADC G Analog Input True, ADC G Analog Input Complement. 5, 6 VIN− H, VIN+ H ADC H Analog Input Complement, ADC H Analog Input True. 9, 10 CLK−, CLK+ Input Clock Complement, Input Clock True. 15, 16 D− H, D+ H ADC H Digital Output Complement, ADC H Digital Output True. 17, 18 D− G, D+ G ADC G Digital Output Complement, ADC G Digital Output True. 19, 20 D− F, D+ F ADC F Digital Output Complement, ADC F Digital Output True. 21, 22 D− E, D+ E ADC E Digital Output Complement, ADC E Digital Output True. 23, 24 DCO−, DCO+ Data Clock Digital Output Complement, Data Clock Digital Output True. 25, 26 FCO−, FCO+ Frame Clock Digital Output Complement, Frame Clock Digital Output True. 27, 28 D− D, D+ D ADC D Digital Output Complement, ADC D Digital Output True. 29, 30 D− C, D+ C ADC C Digital Output Complement, ADC C Digital Output True. 31, 32 D− B, D + B ADC B Digital Output Complement, ADC B Digital Output True. 33, 34 D− A, D+ A ADC A Digital Output Complement, ADC A Digital Output True. 38 SCLK/DTP Serial Clock (SCLK)/Digital Test Pattern (DTP). 39 SDIO/DFS Serial Data Input/Output (SDIO)/Data Format Select (DFS). 40 CSB Chip Select Bar. 41 PDWN Power-Down. 43, 44 VIN+ A, VIN− A ADC A Analog Input True, ADC A Analog Input Complement. 46, 47 VIN− B, VIN+ B ADC B Analog Input Complement, ADC B Analog Input True. 49, 50 VIN+ C, VIN− C ADC C Analog Input True, ADC C Analog Input Complement. 52, 53 VIN− D, VIN+ D ADC D Analog Input Complement, ADC D Analog Input True. Rev. A | Page 9 of 40 Document Outline Features Applications General Description Functional Block Diagram Product Highlights Revision History Specifications DC Specifications AC Specifications Digital Specifications Switching Specifications Timing Specifications Timing Diagrams Absolute Maximum Ratings Thermal Characteristics ESD Caution Pin Configuration and Function Descriptions Typical Performance Characteristics AD9257-65 AD9257-40 Equivalent Circuits Theory of Operation Analog Input Considerations Input Common Mode Differential Input Configurations Voltage Reference Internal Reference Connection External Reference Operation Clock Input Considerations Clock Input Options Input Clock Divider Clock Duty Cycle Jitter Considerations Power Dissipation and Power-Down Mode Digital Outputs and Timing SDIO/DFS Pin SCLK/DTP Pin CSB Pin RBIAS Pin Built-In Output Test Modes Output Test Modes Serial Port Interface (SPI) Configuration Using the SPI Hardware Interface Configuration Without the SPI SPI Accessible Features Memory Map Reading the Memory Map Register Table Open Locations Default Values Logic Levels Channel-Specific Registers Memory Map Register Table Memory Map Register Descriptions Device Index (Register 0x04 and Register 0x05) Transfer (Register 0xFF) Power Modes (Register 0x08) Bits[7:6]—Open Bits[1:0]—Internal Power-Down Mode Enhancement Control (Register 0x0C) Bits[7:3]—Open Bit 2—Chop Mode Bits[1:0]—Open Output Mode (Register 0x14) Bit 7—Open Bit 6—LVDS-ANSI/LVDS-IEEE Option Bits[5:3]—Open Bit 2—Output Invert Bit 1—Open Bit 0—Output Format Output Adjust (Register 0x15) Bits[7:6]—Open Bits[5:4]—Output Termination Bits[3:1]—Open Bit 0—Output Drive Output Phase (Register 0x16) Bit 7—Open Bits[6:4]—Input Clock Phase Adjust Bits[3:0]—Output Clock Phase Adjust Resolution/Sample Rate Override (Register 0x100) User I/O Control 2 (Register 0x101) Bits[7:1]—Open Bit 0—SDIO Pull-Down User I/O Control 3 (Register 0x102) Bits[7:4]—Open Bit 3—VCM Power-Down Bits[2:0]—Open Applications Information Design Guidelines Power and Ground Recommendations Clock Stability Considerations Exposed Pad Thermal Heat Slug Recommendations VCM Reference Decoupling SPI Port Outline Dimensions Ordering Guide