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Adafruit

5.0 (1 review)

$15.80 |
In stock
5.0 (1 review)

The Adafruit Si5351A Clock Generator with STEMMA QT lets you generate precise, arbitrary clock frequencies from 8 kHz to over 150 MHz using a simple I2C inte...

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The Adafruit Si5351A Clock Generator with STEMMA QT lets you generate precise, arbitrary clock frequencies from 8 kHz to over 150 MHz using a simple I2C interface. This updated version adds STEMMA QT / Qwiic connectors for solderless hookup alongside the traditional breadboard headers.

With a precision 25 MHz crystal reference and internal PLLs and dividers, it provides three independent outputs, each configurable to a different frequency with 3 Vpp output levels. Output #1 supports an optional edge-launch SMA connector for RF work. Onboard 3.3 V regulation and I2C level shifting allow use with both 3 V and 5 V systems.

Key Features

  • Si5351A Clock Generator – I2C-controlled with onboard 25 MHz precision crystal reference
  • Wide Frequency Range – 8 kHz to 150+ MHz output
  • 3 Independent Outputs – Each output can be set to a different frequency
  • 3 Vpp Output – Via header pins; output #1 supports optional edge-launch SMA connector
  • STEMMA QT / Qwiic Connectors – Solderless I2C connection and daisy-chaining
  • 3–5 V Power – Onboard 3.3 V LDO regulator and level shifting
  • Arduino & CircuitPython – Library support for both platforms

Also Consider

Ideal For

  • Replacing fixed crystals and oscillators in prototypes
  • RF and radio projects requiring precise clock signals
  • Test and measurement equipment
  • Digital signal processing and clock generation

Package Contents

  • 1× Adafruit Si5351A Clock Generator with STEMMA QT
Note: STEMMA QT / Qwiic cable and SMA connector are not included.

Resources

Jargon buster

Plain-language definitions for the technical terms used above.

CircuitPython
A beginner-friendly version of Python designed to run directly on microcontroller boards. If a product supports CircuitPython, you can often program it by copying code files onto the board rather than setting up a more complex toolchain.
Headers
Rows of connector contacts on a fixed pitch (commonly 2.54 mm) used to link a board to a breadboard, jumper wires, or another board. They come as male pin headers and female socket headers; when a module ships with pre-soldered headers it can be used straight away, whereas bare pads require soldering the pins yourself.
I2C
I2C is a two-wire communication bus used by many sensors and small modules. It matters because several I2C devices can share the same two wires, but each device needs a compatible address and your controller must support I2C.
Qwiic
Qwiic is a plug-in connector system for I2C devices that uses small 4-pin cables, so you can connect compatible sensors without soldering. It matters because your controller or adapter also needs Qwiic, or you will need a cable or breakout to wire it up.
RF
RF means radio frequency, referring to signals used for wireless communication and other high-frequency electronics. A low-noise, stable power supply is important for RF circuits because power noise can affect signal quality and measurements.
SMA
SMA is a small threaded coaxial (RF) connector widely used to attach antennas and other radio-frequency cables. A device with SMA antenna ports needs antennas or pigtails with matching SMA connectors, or a suitable adapter, to connect to them.
STEMMA
A plug-and-cable connection system used on some maker electronics boards to make wiring simpler. If a product uses STEMMA, you need the matching cable or connector type to plug it in without soldering.
STEMMA QT
A small plug-in connector system for I2C boards that lets you connect compatible sensors and controllers without soldering. It matters because it can make wiring faster and less error-prone, especially when adding several small modules to a project.

adafruit si5351 clock generator breakout

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Related Tutorials

Free guides on learn.littlebird.com.au

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