Si5351A Clock Generator Breakout Board - 8KHz to 160MHz

Breakout for the Si5351A clock generator IC with onboard 25MHz crystal reference; internal PLL and dividers produce frequencies from <8KHz to 150+MHz over I2C. Useful for generating arbitrary clock signals without stocking individual crystals.

Logical pinout · physical placement not verified

VIN
Board power input. Adafruit Learn states the onboard regulator accepts 3-5VDC and converts it down for the 3V Si5351A chip.
Type · PowerVoltage · 3-5VDC input, source-backed by Adafruit Learn pinouts
GND
Common ground for power and logic.
Type · GroundVoltage · 0V
SCL
I2C clock line. Adafruit states this pin is level shifted and has a 10K pullup.
Type · I2CVoltage · 3-5V logic
SDA
I2C data line. Adafruit states this pin is level shifted and has a 10K pullup.
Type · I2CVoltage · 3-5V logic
0
Independent generated clock output. Adafruit states the clock outputs are square waves from 0-3V and are also brought out to optional SMA edge-launch connectors.
Type · SignalVoltage · 0-3V square wave output
1
Independent generated clock output. Adafruit states the clock outputs are square waves from 0-3V and are also brought out to optional SMA edge-launch connectors.
Type · SignalVoltage · 0-3V square wave output
2
Independent generated clock output. Adafruit states the clock outputs are square waves from 0-3V and are also brought out to optional SMA edge-launch connectors.
Type · SignalVoltage · 0-3V square wave output

Pin	Type	Function	Voltage
VIN	Power	Board power input. Adafruit Learn states the onboard regulator accepts 3-5VDC and converts it down for the 3V Si5351A chip.	3-5VDC input, source-backed by Adafruit Learn pinouts
GND	Ground	Common ground for power and logic.	0V
SCL	I2C	I2C clock line. Adafruit states this pin is level shifted and has a 10K pullup.	3-5V logic
SDA	I2C	I2C data line. Adafruit states this pin is level shifted and has a 10K pullup.	3-5V logic
0	Signal	Independent generated clock output. Adafruit states the clock outputs are square waves from 0-3V and are also brought out to optional SMA edge-launch connectors.	0-3V square wave output
1	Signal	Independent generated clock output. Adafruit states the clock outputs are square waves from 0-3V and are also brought out to optional SMA edge-launch connectors.	0-3V square wave output
2	Signal	Independent generated clock output. Adafruit states the clock outputs are square waves from 0-3V and are also brought out to optional SMA edge-launch connectors.	0-3V square wave output

Logical pinout · physical placement not verified

Pin details

7 connections

VIN
Board power input. Adafruit Learn states the onboard regulator accepts 3-5VDC and converts it down for the 3V Si5351A chip.
PowerVoltage · 3-5VDC input, source-backed by Adafruit Learn pinouts
GND
Common ground for power and logic.
GroundVoltage · 0V
SCL
I2C clock line. Adafruit states this pin is level shifted and has a 10K pullup.
I2CVoltage · 3-5V logic
SDA
I2C data line. Adafruit states this pin is level shifted and has a 10K pullup.
I2CVoltage · 3-5V logic
0
Independent generated clock output. Adafruit states the clock outputs are square waves from 0-3V and are also brought out to optional SMA edge-launch connectors.
SignalVoltage · 0-3V square wave output
1
Independent generated clock output. Adafruit states the clock outputs are square waves from 0-3V and are also brought out to optional SMA edge-launch connectors.
SignalVoltage · 0-3V square wave output
2
Independent generated clock output. Adafruit states the clock outputs are square waves from 0-3V and are also brought out to optional SMA edge-launch connectors.
SignalVoltage · 0-3V square wave output

RTC & timing

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