Fancy USB LED Vase

The Fancy USB LED Vase functions as an analog relaxation oscillator powered by a standard 5V USB connection. The core of the circuit relies on discrete components arranged to create alternating timing cycles that drive the LED indicators. Power enters the system via the USB B type cable, where decoupling capacitor C4 (100nF ceramic disc) helps stabilize the supply rail against high-frequency noise. The circuit incorporates 2N7000 N-channel MOSFETs (T1-T3) acting as electronic switches. These transistors interface with capacitor networks—using either 2.2µF 16V electrolytic or 47nF ceramic disc options for C1 through C3—to govern the charge and discharge timing intervals. As the capacitors charge and reach the threshold voltage of the respective 2N7000 gate terminals, the MOSFETs transition between states, sequentially turning on and off the connected 5mm LEDs (yellow/amber LED1 and LED3, and green LED2). Current-limiting resistors R1 through R3 (330 ohms) protect the LED junctions from excessive forward current, while resistors R4 through R6 (listed with component values of 1 ohm / 1M ohm in the documentation) establish the necessary bias and timing resistance for the oscillator network. By tuning these RC time constants, the discrete analog hardware produces a dynamic, rotating lighting pattern across the vase without requiring any microcontroller or software programming.