PLL clock buffer with 2:10 fanout
The CY7B9945V-2AC is a PLL-based clock buffer from the Infineon RoboClock series, designed for fanout distribution of a single reference clock to multiple loads. It accepts either LVPECL or LVTTL inputs and provides ten LVTTL outputs, with a maximum operating frequency of 200 MHz. The 2:10 input-to-output ratio means one or two clock sources can be fanned out to ten destinations, reducing the number of oscillators or clock generators needed on the board. The integrated PLL allows for zero-delay or frequency-multiplied/ divided outputs, depending on the configuration.
Signal type conversion and timing
Differential inputs (LVPECL) are accepted, but outputs are single-ended LVTTL. This makes the part useful as a translator between a differential clock source and a single-ended fanout tree, common in systems where the master clock comes from an oscillator or PLL with differential outputs but the downstream logic uses LVTTL. The 200 MHz ceiling sets the upper limit for the clock tree — above that frequency, the output rise/fall times and propagation skew may not meet timing closure. For a 100 MHz DDR bus or a 125 MHz Ethernet reference, the margin is comfortable. The single-circuit design (one PLL core) keeps the power draw predictable — no multiple PLLs competing for lock.
Package and temperature grade
Housed in a 52-lead LQFP (10x10 mm body), the part is suitable for surface-mount assembly with standard reflow profiles. Not rated for industrial or automotive ambient extremes.
Note that this variant is marked as RoHS non-compliant. For lead-free assembly lines, verify the BOM's exemption status or check the RoHS-compliant suffix of the same base part number.