Programmable 3-PLL VCXO clock synthesizer with 2.5-V or 3.3-V LVCMOS outputs

The CDCE937 and CDCEL937 devices are

modular PLL-based low cost, high-performance, programmable clock synthesizers,

multipliers and dividers. The devices generate up to 7 output clocks from a single

input frequency. Each output can be programmed in-system for any clock frequency up

to 230MHz, using up to three independent configurable PLLs.

The CDCEx937 has separate output

supply pins, VDDOUT, which is 1.8V for CDCEL937 and to 2.5V to 3.3V for CDCE937.

The input accepts an external crystal

or LVCMOS clock signal. If an external crystal is used, an on-chip load capacitor is

adequate for most applications. The value of the load capacitor is programmable from

0 to 20pF. Additionally, an on-chip VCXO is selectable which allows synchronization

of the output frequency to an external control signal, that is, PWM signal.