Data SheetAD9251CLK+ttSSYNCHSYNCSYNC 004 07938- Figure 4. SYNC Input Timing Requirements Rev. A | Page 9 of 36 Document Outline FEATURES APPLICATIONS FUNCTIONAL BLOCK DIAGRAM PRODUCT HIGHLIGHTS REVISION HISTORY GENERAL DESCRIPTION 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 AD9251-80 AD9251-65 AD9251-40 AD9251-20 EQUIVALENT CIRCUITS THEORY OF OPERATION ADC ARCHITECTURE ANALOG INPUT CONSIDERATIONS Input Common Mode Differential Input Configurations Single-Ended Input Configuration VOLTAGE REFERENCE Internal Reference Connection External Reference Operation CLOCK INPUT CONSIDERATIONS Clock Input Options Input Clock Divider Clock Duty Cycle Jitter Considerations CHANNEL/CHIP SYNCHRONIZATION POWER DISSIPATION AND STANDBY MODE DIGITAL OUTPUTS Digital Output Enable Function (OEB) TIMING Data Clock Output (DCO) BUILT-IN SELF-TEST (BIST) AND OUTPUT TEST BUILT-IN SELF-TEST (BIST) 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 Transfer Register Map Channel-Specific Registers MEMORY MAP REGISTER TABLE MEMORY MAP REGISTER DESCRIPTIONS Sync Control (Register 0x100) Bits[7:3]—Reserved Bit 2—Clock Divider Next Sync Only Bit 1—Clock Divider Sync Enable Bit 0—Master Sync Enable Bit 7—Enable OEB Pin 47 Bit 3—Enable GCLK Detect Bit 2—Run GCLK Bit 0—Disable SDIO Pull-Down APPLICATIONS INFORMATION DESIGN GUIDELINES Power and Ground Recommendations Exposed Paddle Thermal Heat Sink Recommendations VCM RBIAS Reference Decoupling SPI Port OUTLINE DIMENSIONS ORDERING GUIDE