Si5351 Oscillator Breakout Board

Features

• I2C Daisy-chain connector
• 3 outputs
• 25 or 27 MHz crystal (Rev 1)
• 27 MHz TCXO (Rev 3)
• Can be used as a heat shrinked assembly with cables

Pinout

J1 - Daisy-chained I2C

1. SCL
2. SDA
3. +3.3V
4. GND

J2 - VFO Outputs

• VFO out / GND Pairs

1. VFO0
2. VFO1
3. VFO2

Software

I2C-VFO3 Arduino Code

Measurements

• 10 MHz FFT
  • Square wave has high odd harmonic content

Revision History

Rev 3

• TXCO
• Fixed solder mask clearance

Rev 2

• TXCO instead of crystal
• Insufficient solder mask (too big a clearance)

Rev 1

• Used crystal

Assembly Sheet

Qty	Value	RefDes		Qty	Value	RefDes
2	0.1uF	C1,C2		1	Header, Right Angle, 2x3	J2
2	2.2K	R1,R2		1	Header, Right Angle, 2x4	J1
1	TCXO, 27 MHz ASE-xxxMHz	U2
1	Si5351A	U1