A simple digital circuit project simulating a Traffic Light System using Logisim Evolution. This project demonstrates how binary counters and logic gates control Red, Yellow, and Green lights in a sequence — an ideal beginner’s introduction to VLSI and chip design fundamentals.
The circuit uses a 2-bit counter connected to a clock to generate binary sequences (00, 01, 10, 11). Using AND and NOT gates, these signals control the three lights representing real-world traffic signals.
🟥 Red → 🟩 Green → 🟨 Yellow → repeat ♻️
⚙️ Components Used
2-bit Counter (from Memory section)
Logic Gates (AND, NOT)
Output Pins (as LEDs)
🔩 Working Logic Light Q1 Q0 Logic Expression Red 0 0 NOT Q1 AND NOT Q0 Green 0 1 NOT Q1 AND Q0 Yellow 1 0 Q1 AND NOT Q0
The counter cycles through these binary states, automatically switching the lights in order.
Understanding binary counting and state transitions
Designing sequential circuits with clock and counter
Applying combinational logic to control real-world systems
Gaining hands-on experience with VLSI basics in Logisim
Logisim Evolution v3.7.1 or above
Java 21 or newer (for running Logisim)
Open traffic_light_logisim.circ in Logisim Evolution.
Click Simulate → Tick Enable to start the circuit.
Set Tick Frequency to around 1 Hz for visible timing.
Watch the LEDs cycle through Red → Green → Yellow → Red.
Pranay Anand
Aspiring Python Developer & VLSI Enthusiast Passionate about bridging software intelligence with hardware design.