Pulse extender

Stretch a short pulse into a long one with a delayer and an OR. A ready-made counters circuit you can open in the TorchAnvil simulator.

Making pulses last

Sometimes a signal is too quick to be useful. You press a button, it goes high for a tick, then it's gone — faster than you can blink, and way faster than any downstream circuit can react to. A pulse extender holds the signal high for a little longer, buying you time.

Flip the lever briefly on and off. The lamp lights the instant the lever goes on and stays lit for a few ticks after you flip it off. The circuit stretched your short pulse into a longer one.

How it works

The lever drives two paths at once:

• Direct path: Lever → OR — the lamp responds immediately when the lever goes on.
• Delayed path: Lever → Delayer (3 ticks) → OR — the same signal arrives three ticks later.

The OR gate lights the lamp whenever either path is high. So the lamp goes on the moment you flip the lever, and it stays on until three ticks after the lever goes off — because the delayer is still replaying the "on" value from three ticks ago.

out = In or delayed(In)

Why it matters

This pattern is how you debounce a mechanical switch, how you give a downstream register time to latch a value, and how you shape short detector events into readable pulses. It's also the simplest example of combining the past with the present using a delay line — the building block of every digital filter.

Try this

• Press Run. Flip the lever on and immediately off. The lamp stays lit for a few ticks after your finger is off the switch.
• Click the delayer to change delayTicks (try 1 or 4). Longer delay means a longer extension.
• Hold the lever on for a while, then flip it off. The lamp tails off the same number of ticks later — the "extension" is always the delay length.