The most famous chip in electronics
The 555 timer doing its classic job: blinking an LED about once a second. A good first build.

Free build sheet
The parts, every wire with its length and bend points, a bend guide, both sides of the board and checkboxes to track your progress. Print it or keep it open at the bench.
Open the build sheetWhat you need
9 parts on a perfboard 13 × 25 holes, plus hookup wire.
| Qty | Part | Where to buy |
|---|---|---|
| 1 | Ceramic Cap100nF C1 | Buy Ceramic Cap on Amazon |
| 1 | Ceramic Cap10nF C2 | Buy Ceramic Cap on Amazon |
| 1 | Electrolytic Cap10uF C3 | Buy Electrolytic Cap on Amazon |
| 1 | Power Input (2-pin) J1 | |
| 1 | LED LED1 | Buy LED on Amazon |
| 1 | Resistor (axial)1k R1 | Buy Resistor (axial) on Amazon |
| 1 | Resistor (axial)68k R2 | Buy Resistor (axial) on Amazon |
| 1 | Resistor (axial)470 R3 | Buy Resistor (axial) on Amazon |
| 1 | DIP-8 U1 |
Check every pin against the datasheet of the exact part in your hands before wiring.
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Cut list
14 wires, 373 mm (14.7 in) in total, in the order the build sheet cuts them. Wire numbers match the build sheet. Each length includes 5 mm per end to go through the hole.
| Wire | Colour and net | Length | ||
|---|---|---|---|---|
| 6 | BlackVCC K5 → F5 | K5 → F5 | 23mm | Straight |
| 12 | BlackGND D12 → F18 | D12 → F18 | 30mm | 20mm (90°) |
| 11 | BlueGND C9 → E11 | C9 → E11 | 17mm | Straight |
| 5 | BlueDISCH K11 → D16 | K11 → D16 | 40mm | 23mm (90°) |
| 10 | GreenGND G5 → D8 | G5 → D8 | 21mm | Straight |
| 4 | GreenDISCH J10 → F15 | J10 → F15 | 33mm | 18mm (90°) |
| 7 | RedVCC E4 → C6 | E4 → C6 | 17mm | Straight |
| 13 | RedGND G19 → G23 | G19 → G23 | 20mm | Straight |
| 1 | RedOUT J18 → G11 | J18 → G11 | 35mm | 23mm (90°) |
| 9 | WhiteVCC I12 → E15 | I12 → E15 | 28mm | 13mm (90°) |
| 3 | WhiteTIMING G16 → F11 | G16 → F11 | 35mm | 10mm (90°), 23mm (90°) |
| 2 | YellowTIMING D20 → F17 | D20 → F17 | 23mm | 13mm (90°) |
| 14 | YellowGND H18 → K16 | H18 → K16 | 23mm | 10mm (90°) |
| 8 | YellowVCC J6 → H11 | J6 → H11 | 28mm | 10mm (90°) |
About this build
The 555 timer is the most famous chip in electronics, and this is its classic job: blinking an LED about once a second.
A 10uF capacitor charges through a 1k and a 68k resistor and discharges through the 68k, and the 555 flips its output every time the capacitor crosses one of its thresholds. The output drives the LED through a 470 ohm resistor.
Two small caps keep it steady, a 100nF across the supply and a 10nF on the control input. It runs from 9V, laid out from the input at the top down to the LED at the bottom.
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