stays on 12 ticks (0.6 s) after · 17 blocks

The output turns on with the input and stays on 12 ticks (0.6 s) after the input turns off.

needs an input of at least 4 ticks (0.2 s) · made of comparator, redstone wire · fits in 3×2×4

stays on 12 ticks (0.6 s) afterStay-on timer3D view loading (or not available in this browser)

Every size 9

The best design for each size: pick one to see it.

size	blocks	numbers
4 ticks (0.2 s)	21 blocks	needs an input of at least 4 ticks (0.2 s)
8 ticks (0.4 s)	17 blocks	needs an input of at least 4 ticks (0.2 s)
12 ticks (0.6 s) (this page)	17 blocks	needs an input of at least 4 ticks (0.2 s)
16 ticks (0.8 s)	14 blocks	needs an input of at least 4 ticks (0.2 s)
20 ticks (1 s)	17 blocks	needs an input of at least 4 ticks (0.2 s)
24 ticks (1.2 s)	13 blocks	needs an input of at least 4 ticks (0.2 s)
28 ticks (1.4 s)	13 blocks	needs an input of at least 4 ticks (0.2 s)
108 ticks (5.4 s)	28 blocks	needs an input of at least 3 ticks (0.15 s)
990 ticks (49.5 s), needs a long input	8 blocks	needs an input of at least 1,280 ticks (1 min 4 s)

Try it

Tap IN under the view to turn the input on, again to turn it off: turn it on, then off: OUT stays red a while after (the box marked OUT turns red while the output is on). Press play under the view to watch a demo on a loop; touch any other control to take over.

How this design does it: Keeps its output on for 12 ticks after the input turns off: two comparators pass the signal around a small loop, and the dust in the loop weakens it on every lap until it dies out.

Build it

Download .litematic Download the design as text

The .litematic opens in Litematica (Minecraft 26.3): every block of the design in one region. The text file is the same build written as plain text, block by block.

Blocks used: comparator redstone wire stone

Details: how it works, measurements and properties

In depth

The output turns on with the input (in the same game tick) and stays on 12 ticks (0.6 s) after the input turns off: every output pulse is the input's length plus 12 ticks (0.6 s). Input pulses closer together than that merge into one long output pulse (a light or a door that stays on a while after the last press of a pressure plate).

It reacts to input pulses of 4 ticks (0.2 s) or longer.

How to try it

Press play under the view to watch the demo on a loop: input pulses of 1 to 80 ticks (4 s) (each output pulse lasts 12 ticks (0.6 s) longer than its input), then groups of 3 short pulses with growing gaps (closer than L, they merge into one output pulse). The badge reads demo with the step it is on, and the same sequence is drawn as a timing diagram below. Touch any control to stop it and try the circuit yourself.

To try it: tap the IN button of the bar (or the cell tagged IN) to turn that input on or off (it powers the cell with a redstone block): turn the input on, then off: the output stays on 12 ticks (0.6 s) after you turn it off.

Inputs are tagged in lime; the output is tagged OUT: the redstone lamp in that cell (the view adds it to show the output) lights while the output is on (the output strip by the demo badge shows its last 40 game ticks, 2 seconds). Drag to look around, pinch or scroll to zoom, step one game tick at a time with the step button.

Inputs and output over time

The input follows this schedule (the 3D view's demo plays the same). Lime: an input is on; orange: the output is on (taller = a stronger signal, 1 to 15). Time runs left to right in game ticks (20 ticks = 1 s).

Swipe the diagram sideways: the whole sequence lasts 1106 ticks (55.3 s).

Step by step (18 lines)

in  2 ticks (0.1 s): +0 for 2
in  3 ticks (0.15 s): +0 for 3, +4 for 11
in  4 ticks (0.2 s): +0 for 16
in  5 ticks (0.25 s): +0 for 17
in  6 ticks (0.3 s): +0 for 18
in  8 ticks (0.4 s): +0 for 20
in 10 ticks (0.5 s): +0 for 22
in 15 ticks (0.75 s): +0 for 27
in 20 ticks (1 s): +0 for 32
in 30 ticks (1.5 s): +0 for 42
in 40 ticks (2 s): +0 for 52
in 60 ticks (3 s): +0 for 72
in 80 ticks (4 s): +0 for 92
3 inputs 2 ticks (0.1 s) apart: +0 for 28
3 inputs 4 ticks (0.2 s) apart: +0 for 32
3 inputs 8 ticks (0.4 s) apart: +0 for 40
3 inputs 16 ticks (0.8 s) apart: +0 for 16, +20 for 16, +40 for 16
3 inputs 32 ticks (1.6 s) apart: +0 for 16, +36 for 16, +72 for 16

Measurements

metric	value	what it means
L	12 ticks (0.6 s)	how long the output stays on after the input turns off
latency	0 ticks (0 s)	game ticks from the input turning on to the output turning on
min-pulse	4 ticks (0.2 s)	the shortest input pulse handled correctly (every longer one works too)

Notes from its designer

Keeps its output on for 12 ticks after the input turns off: two comparators pass the signal around a small loop, and the dust in the loop weakens it on every lap until it dies out. Unlike the 6-block item timer, it restarts from a 2-tick input and times in 2-tick steps. Details: 5 dust carry the second comparator's output back to the first, losing 4 signal strength per 4-tick lap; while the input is on it keeps the loop full; the comparator the output reads sets the exact length.

Properties

Study	Timers and pulse multipliers
Kind	Stay-on timer (off-delay)
Blocks placed	17 (not counting the input levers or buttons and the lamp the view adds)
Box	3×2×4 (24 blocks of space)
Made of (the blocks that change state)	comparator, redstone wire
Inputs / outputs	IN (repeater) / OUT
Flags	instant (reacts in the same tick)
Design file	`off-delay-ring-L12`

The design file

on GitHub

Design file (27 lines)

# Stay-on timer: stays on 12 ticks (0.6 s) after · 17 blocks
# https://vjeux.github.io/redstonepedia/circuits/pulsemult/off-delay-ring-L12.html
name: off-delay-ring-L12
circuit: off-delay
origin: -1 0 0
port input: 1 1 4
port output: -1 1 3
palette:
  S minecraft:stone
  d minecraft:redstone_wire[east=side,north=side,power=0,south=side,west=side]
  E minecraft:comparator[facing=east,mode=compare,powered=false]
  n minecraft:comparator[facing=north,mode=compare,powered=false]
  O minecraft:observer[facing=east,powered=false]
  U minecraft:observer[facing=up,powered=false]
  B minecraft:waxed_copper_bulb[lit=false,powered=false]
layer 0:
  ..S.
  .S.S
  ...S
  .SSS
  ....
layer 1:
  .SES
  .n.d
  .S.d
  .ddd
  ....