Qwiic Digital Capacitor - NCD2400M

The Qwiic Digital Capacitor makes it easy to fine-tune oscillator circuits and RF filters without repeatedly swapping physical capacitors. Built around the NCD2400M IC, this board lets you adjust capacitance from 1.7 pF to 200 pF via I²C — solder the nibs onto any 0603 or 0402 footprint, plug in a Qwiic cable, and change the value in code.

Using the Arduino library, you can set and read capacitance, choose between shunt and series configuration modes, and write to volatile or non-volatile memory. The Qwiic connector means no soldering for the I²C connection — just plug and go with automatic voltage regulation and translation.

Key Features

• NCD2400M IC – Digitally programmable capacitor, 1.7–200 pF
• I²C Control – Set capacitance in code via Qwiic/I²C interface
• Shunt or Series Mode – Configurable topology for your circuit
• Volatile and Non-Volatile Memory – Store settings temporarily or permanently
• Qwiic Compatible – Plug-and-play with no soldering for the I²C connection
• 0603/0402 Footprint – Solder nibs directly onto standard capacitor pads

Ideal For

• Tuning oscillator circuits and RF filters
• Automated capacitance sweeping and testing
• Prototyping variable-capacitance designs

Resources

• Arduino Library (GitHub)
• SparkFun Forum