laboratoryofplasmaphysics / sticky

Sticky: A Low-Frequency Noise Measurement Board for Amplifiers

Sticky: A Low-Frequency Noise Measurement Board for Amplifiers

Sticky is a compact and easy-to-use open-source board designed for low-frequency noise measurement of amplifiers. It operates from 0.001 Hz to 50 kHz max and is capable of high-resolution data acquisition. This board has been designed mainly to perform noise measurement of amplifiers designed in our laboratory, such as this one.

Key Features

• Low frequency noise measurements (from 0.001Hz to 50kHz max)
• Fully open-source board, from PCB design to firmware.
• Affordable - under 100€ per board.
• Small and USB powered.

This PCB uses:

• THS4551 as a matching input buffer for ADC: The choice of THS4551 was driven by the ADC and its excellent noise performance.
• ADS9224R for analog to digital conversion: ADS9224R offers a good compromise between performance (16bits @ 3MSps) and a relatively low price and simple interface.
• ICE40HX4K-TQ144 to drive the ADC: An FPGA was chosen to ensure low jitter continuous sampling, and it can later implement some basic digital filtering.
• FT2232HL as a USB2 bridge: FT2232HL is used both to flash the FPGA and send data back to a computer continuously @ 2MSps.

PCB V1.1 preview:

Noise and Total Harmonic Distortion Measurements

The Sticky board has excellent noise performance (~100nV/sqrt(Hz) after 100Hz) and reasonably low 1/f noise, making it suitable for measuring low-frequency signals. This measurement has been done with both inputs open. The Sticky board also has low harmonic distortion (~0.03% THD), making it an excellent tool for measuring amplifier performance.

License

Sticky is licensed under CC-BY-SA. Feel free to use, modify, and distribute this board. If you use Sticky in any of your projects, we would appreciate it if you could attribute it to us.