DLD: Logic Design & Circuits

DLD is a digital logic design and circuits workbench for your phone. Drop gates onto the
bench, wire them together, flip a switch, and watch the signal travel through
the circuit in real time.

Built for students working through a digital logic design course — and for
anyone who wants to see Boolean algebra actually do something.

BUILD ANYTHING
• 28 components: switches, clocks, Vcc and ground, every standard gate,
tri-state buffers, multiplexers, flip-flops, displays and probes
• Gates take 2 to 8 inputs — one wide NAND instead of three cascaded ones
• Tap a component to reach its settings: input count, clock speed, colour
• A work bench far bigger than the screen, with pan, zoom and fit-to-circuit

SEE IT WORKING
• Current animates along every live wire, so you can follow a signal
• LEDs, LED bars, 7-segment and hex displays light up as the circuit runs
• A school bell that rings for as long as it has current
• Logic probes read out 1 or 0 anywhere you wire one

UNDERSTAND IT
• Boolean equations written out from whatever you have drawn
• A full truth table generated from your circuit, ready to copy out
• Conflicting drivers on a net are flagged rather than quietly wrong
• A tutorial section covering every gate symbol and its truth table

KEEP YOUR WORK
• Save and reopen as many circuits as you like
• Undo and redo everything
• Recolour wires, lamps and blocks however you want to read them

COMPONENTS
Switch · Clock · Vcc · GND · AND · OR · NOT · NAND · NOR · XOR · XNOR ·
Buffer · Tri-state buffer · Tri-state NOT · MUX · DEMUX · D flip-flop ·
T flip-flop · JK flip-flop · Virtual links · LED · LED bar · 7-segment ·
Hex display · Bell · Probe · Label

PRIVATE BY DEFAULT
No account. No sign-in. No analytics. No ads. Nothing leaves your device —
your circuits are saved on the phone and nowhere else. The app works with no
network connection at all.