SI53321-B-GQ

Clock Buffers, Drivers Overview

The SI53321-B-GQ is a low-jitter LVPECL fanout clock buffer from the Si5332x family, manufactured by Skyworks Solutions. It features ten LVPECL outputs and accepts any-format inputs including LVPECL, LVDS, CML, HCSL, and LVCMOS via a universal input stage. The device includes a 2:1 input multiplexer for redundant clocking and operates over a frequency range of DC to 1250 MHz. It utilizes built-in LDOs for high power supply noise rejection (PSRR) and is housed in a 32-eLQFP package measuring 7 x 7 mm.

Clock Buffers, Drivers Feature Summary

• Ultra-low additive jitter performance with typical values of 50 fs rms
• Universal input termination supporting multiple formats (LVPECL, LVDS, CML, HCSL, LVCMOS)
• Built-in 2:1 input mux for selectable clock sources
• Integrated LDOs providing high PSRR for noisy environments

Clock Buffers, Drivers Applications

• Clock and data distribution systems
• Redundant clocking architectures
• High-speed digital interfaces requiring low-skew buffering

Clock Buffers, Drivers Procurement Notes

Verify the specific ordering suffix -GQ corresponds to the 32-eLQFP (7 x 7 mm) package configuration as listed in the official Skyworks Si5332x ordering guide. Confirm that the required operating temperature range of –40 to +85 °C aligns with the system design specifications before procurement.

Clock Buffers, Drivers Selection Notes

Select this component when an application requires up to ten LVPECL outputs driven by diverse input signal formats. Ensure the input source provides a sufficient slew rate (minimum 0.75 V/ns for differential, 1.0 V/ns for single-ended) to maintain specified jitter performance. Verify that the PCB layout accommodates the 32-eLQFP footprint and that power supply filtering meets the internal LDO requirements.

Clock Buffers, Drivers Part Context

This part belongs to the Si53320–28 family of fixed-format LVPECL buffers. Unlike programmable generators in the broader Si5332 series, these devices function strictly as fanout buffers. They are designed to be paired with Si534x clocks or Si5xx oscillators to establish complete end-to-end clock trees with optimized jitter characteristics.

Clock Buffers, Drivers Replacement Considerations

The SI53321-B-GM serves as a direct functional substitute within the same family, offering identical electrical specifications but utilizing a 32-QFN (5 x 5 mm) package instead of the eLQFP form factor.