AD6649EBZ datasheet(28/40 Pages) AD

28 / 40 page

AD6649

Rev. 0 | Page 28 of 40

CHANNEL/CHIP SYNCHRONIZATION

The AD6649 has a SYNC input that allows the user flexible syn-

chronization options for synchronizing the internal blocks. The

SYNC feature is useful for guaranteeing synchronized operation

across multiple ADCs. The input clock divider, NCO, FIR filters,

and the output fS/4 NCO can be synchronized using the SYNC

input. Each of these blocks can be enabled to synchronize on a

single occurrence of the SYNC signal or on every occurrence by

setting the appropriate bits in Register 0x58.

The SYNC input is internally synchronized to the sample clock.

However, to ensure that there is no timing uncertainty between

multiple parts, the SYNC input signal should be synchronized

to the input clock signal. The SYNC input should be driven

using a single-ended CMOS type signal.

If Bit 1 in Register 0x59 is used, the SYNC input can be set to

either level or edge sensitive mode. If the SYNC input is set to

edge sensitive mode, Bit 0 of Register 0x59 can be used to

determine whether the rising or falling edge is used.

AD6649EBZ Datasheet(PDF) 28 Page - Analog Devices