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SI5351A-B-GMR

SI5351A-B-GMR

Skyworks Solutions Inc.
Clock Generator IC 200MHz 2 20-VFQFN Exposed Pad
Active8,951 in stock
Datasheet Digi-Key Mouser Compare Prices

Overview

The SI5351A-B-GMR is a highly flexible, I2C-programmable CMOS clock generator capable of synthesizing up to 8 non-integer-related frequencies from 8 kHz to 200 MHz. It uses a dual-PLL architecture with patented MultiSynth fractional dividers to achieve 0 ppm frequency synthesis error while operating from a low-cost 25 or 27 MHz crystal.

Why Choose This Part

This IC offers excellent PSRR, eliminating the need for expensive external power supply filtering while maintaining low power consumption at 27mA with all outputs active. Its ability to provide level translation through separate voltage supply pins for each output bank simplifies multi-voltage designs.

Applications

Audio/Video Equipment
Replacing multiple discrete crystal oscillators with a single IC to generate disparate clock frequencies for DSPs and DACs.
SDR and Radio Prototyping
Generating precise local oscillator signals for radio frequency synthesis in amateur radio and software-defined radio applications.
Networking and Storage
Providing reference clocks for Ethernet, PCIe Gen 1, and fibre channel controllers with configurable spread spectrum for EMI reduction.
Embedded System Master Clocks
Acting as a centralized timing source for complex PCBs requiring multiple clock domains at varying voltage levels.

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

Initialize the device via the I2C interface to configure the PLL and MultiSynth registers using the Skyworks ClockBuilder Pro software tool. For prototyping, the Adafruit Si5351A breakout board provides an easy hardware entry point for use with MCU-based drivers.

SI5351A-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
SI5351A-B-GMR (this part) VFQFN-20 Clock Generator Crystal 1.71V 2 1:8 8,951
SI5351A-B-GM VFQFN-20 Clock Generator Crystal 1.71V 2 1:8 637
SI5351A-B-GM1 (Skyworks Solutions, Inc.) VFQFN-16 Clock Generator, V.. Clock, Crystal 2.25V 1 1:4 272
Also available as: SI5351A-B-GT

Also Consider

SI5351A-B-GT Skyworks Solutions Inc. - This is the MSOP-10 package version, which is easier to hand-solder than the VFQFN variant.
SI5351B-B-GMR Skyworks Solutions Inc. - Choose this variant if an integrated VCXO is required for frequency tuning applications.

Categories

Clocks & Timing > Clock Generators & PLLs
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