PLL-based zero delay buffer for clock distribution
The Infineon CY2304SI-2 is a PLL-based zero delay buffer designed to regenerate a clock input with deterministic phase alignment, fanning out one clock source to four outputs at up to 133 MHz.
133 MHz fan-out with 1:4 ratio
The 1:4 input-to-output ratio means one clock input drives four output copies, each phase-locked to the reference — useful for distributing a master clock to multiple FPGAs, ASICs, or memory interfaces on the same board. With no differential I/O, the buffer accepts single-ended clock inputs and delivers single-ended outputs, keeping the routing simple on a standard 2- or 4-layer PCB. The divider/multiplier is listed as Yes/No, indicating the device can divide the input frequency but does not multiply it — the output frequency is equal to or a sub-multiple of the input, not a higher multiple.
8-SOIC package and supply integration
The single-circuit design (one PLL core) drives all four outputs from one clock tree, simplifying decoupling — a single 0.1 µF cap near the supply pin per the datasheet recommendation is typical.
Active lifecycle and compliance note
The device is marked RoHS non-compliant — a legacy BOM flag for designs that still permit tin-lead solder processes or require lead-bearing finishes for high-reliability applications.