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SI5351B-B-GMR

SI5351B-B-GMR

Skyworks Solutions Inc.
Clock Generator IC 200MHz 2 20-VFQFN Exposed Pad
Active3,828 in stock
Datasheet Digi-Key Mouser Compare Prices

Overview

The SI5351B-B-GMR is a highly flexible, I2C-programmable clock generator that combines a VCXO and a PLL-based frequency synthesizer into a single IC. It can generate up to 8 independent frequencies ranging from 8 kHz to 200 MHz with 0 ppm synthesis error, making it a replacement for multiple crystals and oscillators. This 'B' variant specifically includes an integrated Voltage Controlled Crystal Oscillator (VCXO) for applications requiring frequency synchronization or tuning.

Why Choose This Part

The SI5351B provides glitchless frequency changes and adjustable output delays to manage clock skew across the PCB. Its excellent PSRR reduces the need for complex external power supply filtering while consuming only 27mA with all eight outputs active. The I2C interface allows for real-time reconfiguration of spread spectrum and phase offset parameters.

Applications

Multi-Oscillator Replacement
Consolidate multiple crystals and oscillators into a single 20-QFN footprint to save board space and reduce BOM cost.
Audio/Video Synchronization
Utilize the internal VCXO to synchronize system clocks to an external reference or video frame rate.
PCI Express Clocking
Generate PCIe Gen 1 compliant clocks for embedded computing and networking peripherals.
Level Translation
Use the separate voltage supply pins (VDDO) to output CMOS levels from 1.71V to 3.6V independent of the core supply.

Key Specifications

PLL Yes
Type Clock Generator
Input Crystal
Output LVCMOS
Mounting Type Surface Mount
Package / Case 20-VFQFN Exposed Pad
Frequency - Max 200MHz
Voltage - Supply 1.71V ~ 3.6V
Divider/Multiplier Yes/No
Number of Circuits 2
Ratio - Input:Output 1:8
Operating Temperature -40degC ~ 85degC
Supplier Device Package 20-QFN (4x4)
Differential - Input:Output No/No

Getting Started

Implementation requires an external 25 MHz or 27 MHz crystal as the timing reference. Engineers can use Skyworks' ClockBuilder Pro software to generate the register configuration maps, which are then loaded into the device over the I2C bus. Ensure the exposed pad is properly soldered to the ground plane for thermal and electrical performance.

Part of Si5351 Clock Generators family » SI5351B-B

SI5351B-B Family

Comparing specs that differ across variants. The current part is highlighted.

Part Number Package Type Input Voltage Number of Circuits Ratio - Input:Output Stock
SI5351B-B-GMR (this part) VFQFN-20 Clock Generator Crystal 1.71V 2 1:8 3,828
SI5351B-B-GM1 VFQFN-16 Clock Generator, V.. Clock, Crystal 2.25V 1 1:4 —
Also available as: SI5351B-B-GM

Also Consider

Si5351A-B-GT Skyworks Solutions Inc. - Select this variant if the VCXO functionality is not required and a smaller 10-MSOP package is preferred for basic clock synthesis.

Categories

Clocks & Timing > Clock Generators & PLLs