Datasheet AD9251 (Analog Devices) - 9

AD9251 Data Sheet TIMING SPECIFICATIONS Table 5. Parameter Conditions Min Typ Max Unit
SYNC TIMING REQUIREMENTS tSSYNC SYNC to rising edge of CLK setup time 0.24 ns tHSYNC SYNC to rising edge of CLK hold time 0.40 ns SPI TIMING REQUIREMENTS tDS Setup time between the data and the rising edge of SCLK 2 ns tDH Hold time between the data and the rising edge of SCLK 2 ns tCLK Period of the SCLK 40 ns tS Setup time between CSB and SCLK 2 ns tH Hold time between CSB and SCLK 2 ns tHIGH SCLK pulse width high 10 ns tLOW SCLK pulse width low 10 ns tEN_SDIO Time required for the SDIO pin to switch from an input to an 10 ns output relative to the SCLK falling edge tDIS_SDIO Time required for the SDIO pin to switch from an output to an 10 ns input relative to the SCLK rising edge
Timing Diagrams N – 1 N + 4 tA N + 5 N N + 3 VIN N + 1 N + 2 tCH tCLK CLK+ CLK– tDCO DCOA/DCOB tSKEW CH A/CH B DATA N – 9 N – 8 N – 7 N – 6 N – 5
002
tPD
07938- Figure 2. CMOS Output Data Timing
N – 1 N + 4 tA N + 5 N N + 3 VIN N + 1 N + 2 tCH tCLK CLK+ CLK– tDCO DCOA/DCOB tSKEW CH A/CH B DATA CH A CH B CH A CH B CH A CH B CH A CH B CH A AS APPEARS ON N – 9 N – 9 N – 8 N – 8 N – 7 N – 7 N – 6 N – 6 N – 5 CH A OUTPUT PINS
003
tPD
07938- Figure 3. CMOS Interleaved Output Timing, Output as Appears on Channel A Output Pins Rev. A | Page 8 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