Adafruit ADG728 1-to-8 Analog Matrix Switch - Stemma QT

Analog switches offer a solid state alternative to mechanical relays, providing a smaller, lower-power, and wear-free technology for switching analog signals. The Adafruit ADG728 1-to-8 Analog Matrix Switch allows you to connect up to eight analog signals via independent switches controlled through I2C.

This breakout board enables easy use of the ADG728 chip for signals up to 5V without any soldering, featuring the STEMMA QT connector for easy, solderless connections. The ADG728 is a matrix switch with 8 independent switches, not just a multiplexer, allowing multiple signals to be merged or individually switched.

Key features include near-instant switching (approximately 100ns), break-before-make switching to avoid signal contention, and bidirectional signal paths. The board includes I2C address pins for changing the address and a reset pin to open all channels immediately.

Important usage notes:

• The power input (Vin) must be at least as high as the highest voltage you intend to switch (e.g., 5V for 5V signals).
• Negative voltages are not supported on switched signals.
• This is a signal switch, not a power switch; it is not designed to source or sink more than a few milliamps of current.

Technical specifications:

• I2C interface
• Operating voltage from 2.7V to 5.5V
• On resistance 2.5 Ω
• On-resistance flatness 0.75 Ω
• Leakage currents approximately 100 pA
• Single 8-to-1 matrix switch
• Power-on reset function
• Compact dimensions: 30.6mm x 17.8mm x 4.7mm
• Lightweight at 2.1g

Compatible with the STEMMA QT and SparkFun Qwiic I2C connector standards for easy integration.