Datasheet Analog Devices AD9551

Multiservice Clock Generator
AD9551
Reference conditioning and switchover circuitry internally
synchronizes the two references so that if one reference fails,
there is virtually no phase perturbation at the output. FEATURES
Translation between any two standard network rates
Dual reference inputs and dual clock outputs
Pin programmable for standard network rate translation
SPI programmable for arbitrary rational rate translation
Output frequencies from 10 MHz to 900 MHz
Input frequencies from 19.44 MHz to 806 MHz
On-chip VCO
Meets OC-192 high band jitter generation requirement
Supports standard forward error correction (FEC) rates
Supports holdover operation
Supports hitless switchover and phase build-out (even with
unequal reference frequencies)
SPI-compatible 3-wire programming interface
Single supply (3.3 V) The AD9551 uses an external crystal and an internal DCXO to
provide for holdover operation. If both references fail, the device
maintains a steady output signal.
The AD9551 provides pin-selectable, preset divider values for
standard (and FEC adjusted) network frequencies. The pinselectable frequencies include any combination of 15 possible …