This is a microcontroller project to measure and plot the current/voltage curve for a two-terminal device. It uses Arduino-based hardware to apply different voltages to a device and measure the current that flows through it. The data is captured over the serial monitor and fed through a Python script that plots the graph. Here is an example using a 3V Zener diode:
See the article I wrote explaining this project: Build A Homebrew Current/Voltage Plotter