Red LED Blinker Circuit Design

brooks

Make a circuit that blinks a red LED once per second.

Power it with a 9V block battery through an on/off switch.

Use components that are easy to hand-solder.

flux

0:26

Thought for 2 sec

Thought for 7 sec

Thought for a moment

I’ll build a through-hole 555 astable LED blinker for a 9V battery: select hand-solderable parts, calculate ~1 Hz timing, wire the schematic with required 555 bypass/decoupling, then run checks.

flux

6:52

Thought for 2 sec

Created 5 tasks.

Thought for 2 sec

1/5 Rename project and create a concise design record

Thought for 3 sec

Thought for 6 sec

Thought for 4 sec

Thought for 2 sec

2/5 Select through-hole components and calculate 1 Hz 555 timing/current values

Thought for 6 sec

Ran calculation.

Thought for 5 sec

Found 2 results for NE555 or LM555 timer IC in through-hole DIP-8 package for 9V astable LED blinker, hand solderable, common hobby part.

Found 2 results for red through-hole 5mm LED hand solderable indicator for 9V 555 timer blinker.

Found 3 results for through-hole SPST slide switch or toggle switch for 9V battery on off power switch hand solderable.

Found 3 results for 9V battery snap connector or clip through-hole leads for PCB power input hand solderable.

Thought for 6 sec

Found 3 results for Generic Resistor.

Found 3 results for Generic Capacitor.

Thought for 6 sec

3/5 Add hand-solderable components to the schematic

Thought for 14 sec

Thought for 7 sec

Thought for 3 sec

4/5 Wire 9V battery, switch, 555 astable, decoupling, and LED output

Thought for 2 sec

Thought for 5 sec

Thought for 8 sec

Thought for 5 sec

5/5 Run schematic review and fix violations

Thought for 10 sec

Completed design checks — found 18 issues.

Read schematic.

Thought for 17 sec

Thought for 7 sec

Thought for a moment

Completed design checks — found 11 issues.

Thought for 17 sec

Thought for 5 sec

5/5 tasks completed.

Thought for a moment

Done — I created the through-hole 9V NE555 red LED blinker schematic, added the battery snap and on/off switch, wired the full astable circuit with required 555 bypass/decoupling, and fixed the review issue by assigning MPNs to the passives.

Review is clean: no matching ERC/manufacturing warnings or errors. I also updated Design Notes with the parts, wiring summary, and timing/current calculations.

Start PCB layout

Make it smaller

Add mounting holes

Use AA batteries

Add enclosure switch

Finished working

GND

Resistance

680Ω

Capacitance

10µF

Resistance

1kΩ

Capacitance

100nF

Resistance

680kΩ

Capacitance

10nF

Capacitance

1µF

U1 OUT - R3 P1

R1 P2 - R2 P1

R2 P2 - C1 P1

SW1 NO - U1 VCC

R3 P2 - D1 A

U1 CONT - C2 P1

BT1 POS - SW1 COM

SW1 NO - U1 VCC

U1 CONT - C2 P1

R2 P2 - C1 P1

BT1 POS - SW1 COM

R1 P2 - R2 P1

SW1 NO - U1 VCC

R2 P2 - C1 P1

SW1 NO - U1 VCC

R1 P2 - R2 P1

U1 OUT - R3 P1

R3 P2 - D1 A

SW1 NO - U1 VCC

BT1

SW1

Reviews

Generic Inductor
A generic fixed inductor suitable for rapid circuit topology development. The footprint automatically adapts based on the selected package, supporting standard SMD sizes (e.g., 0402, 0603, 0805) as well as well-known inductor packages such as SDR1806, PA4320, SRN6028, and SRR1260. Standard inductor values: 1.0 nH, 10 nH, 100 nH, 1.0 µH, 10 µH, 100 µH, 1.0 mH 1.2 nH, 12 nH, 120 nH, 1.2 µH, 12 µH, 120 µH, 1.2 mH 1.5 nH, 15 nH, 150 nH, 1.5 µH, 15 µH, 150 µH, 1.5 mH 1.8 nH, 18 nH, 180 nH, 1.8 µH, 18 µH, 180 µH, 1.8 mH 2.2 nH, 22 nH, 220 nH, 2.2 µH, 22 µH, 220 µH, 2.2 mH 2.7 nH, 27 nH, 270 nH, 2.7 µH, 27 µH, 270 µH, 2.7 mH 3.3 nH, 33 nH, 330 nH, 3.3 µH, 33 µH, 330 µH, 3.3 mH 3.9 nH, 39 nH, 390 nH, 3.9 µH, 39 µH, 390 µH, 3.9 mH 4.7 nH, 47 nH, 470 nH, 4.7 µH, 47 µH, 470 µH, 4.7 mH 5.6 nH, 56 nH, 560 nH, 5.6 µH, 56 µH, 560 µH, 5.6 mH 6.8 nH, 68 nH, 680 nH, 6.8 µH, 68 µH, 680 µH, 6.8 mH 8.2 nH, 82 nH, 820 nH, 8.2 µH, 82 µH, 820 µH, 8.2 mH #generics #CommonPartsLibrary
jharwinbarrozo
16.1k
Generic Capacitor
A generic fixed capacitor ideal for rapid circuit topology development. You can choose between polarized and non-polarized types, its symbol and the footprint will automatically adapt based on your selection. Supported options include standard SMD sizes for ceramic capacitors (e.g., 0402, 0603, 0805), SMD sizes for aluminum electrolytic capacitors, and through-hole footprints for polarized capacitors. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard capacitor values: 1.0pF, 10pF, 100pF, 1000pF, 0.01uF, 0.1uF, 1.0uF, 10uF, 100uF, 1000uF, 10000uF 1.1pF, 11pF, 110pF, 1100pF 1.2pF, 12pF, 120pF, 1200pF 1.3pF, 13pF, 130pF, 1300pF 1.5pF, 15pF, 150pF, 1500pF, 0.015uF, 0.15uF, 1.5uF, 15uF, 150uF, 1500uF 1.6pF, 16pF, 160pF, 1600pF 1.8pF, 18pF, 180pF, 1800pF 2.0pF, 20pF, 200pF, 2000pF 2.2pF, 22pF, 220pF, 2200pF, 0.022uF, 0.22uF, 2.2uF, 22uF, 220uF, 2200uF 2.4pF, 24pF, 240pF, 2400pF 2.7pF, 27pF, 270pF, 2700pF 3.0pF, 30pF, 300pF, 3000pF 3.3pF, 33pF, 330pF, 3300pF, 0.033uF, 0.33uF, 3.3uF, 33uF, 330uF, 3300uF 3.6pF, 36pF, 360pF, 3600pF 3.9pF, 39pF, 390pF, 3900pF 4.3pF, 43pF, 430pF, 4300pF 4.7pF, 47pF, 470pF, 4700pF, 0.047uF, 0.47uF, 4.7uF, 47uF, 470uF, 4700uF 5.1pF, 51pF, 510pF, 5100pF 5.6pF, 56pF, 560pF, 5600pF 6.2pF, 62pF, 620pF, 6200pF 6.8pF, 68pF, 680pF, 6800pF, 0.068uF, 0.68uF, 6.8uF, 68uF, 680uF, 6800uF 7.5pF, 75pF, 750pF, 7500pF 8.2pF, 82pF, 820pF, 8200pF 9.1pF, 91pF, 910pF, 9100pF #generics #CommonPartsLibrary
jharwinbarrozo
1.5M
Generic Resistor
A generic fixed resistor ideal for rapid circuit topology development. Its footprint automatically adapts based on the selected package case code—supporting 0402, 0603, 0805, 1203, and many other standard SMD packages, as well as axial horizontal and vertical configurations. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard resistor values: 1.0 ohm, 10 ohm, 100 ohm, 1.0k ohm, 10k ohm, 100k ohm, 1.0M ohm 1.1 ohm, 11 ohm, 110 ohm, 1.1k ohm, 11k ohm, 110k ohm, 1.1M ohm 1.2 ohm, 12 ohm, 120 ohm, 1.2k ohm, 12k ohm, 120k ohm, 1.2M ohm 1.3 ohm, 13 ohm, 130 ohm, 1.3k ohm, 13k ohm, 130k ohm, 1.3M ohm 1.5 ohm, 15 ohm, 150 ohm, 1.5k ohm, 15k ohm, 150k ohm, 1.5M ohm 1.6 ohm, 16 ohm, 160 ohm, 1.6k ohm, 16k ohm, 160k ohm, 1.6M ohm 1.8 ohm, 18 ohm, 180 ohm, 1.8K ohm, 18k ohm, 180k ohm, 1.8M ohm 2.0 ohm, 20 ohm, 200 ohm, 2.0k ohm, 20k ohm, 200k ohm, 2.0M ohm 2.2 ohm, 22 ohm, 220 ohm, 2.2k ohm, 22k ohm, 220k ohm, 2.2M ohm 2.4 ohm, 24 ohm, 240 ohm, 2.4k ohm, 24k ohm, 240k ohm, 2.4M ohm 2.7 ohm, 27 ohm, 270 ohm, 2.7k ohm, 27k ohm, 270k ohm, 2.7M ohm 3.0 ohm, 30 ohm, 300 ohm, 3.0K ohm, 30K ohm, 300K ohm, 3.0M ohm 3.3 ohm, 33 ohm, 330 ohm, 3.3k ohm, 33k ohm, 330k ohm, 3.3M ohm 3.6 ohm, 36 ohm, 360 ohm, 3.6k ohm, 36k ohm, 360k ohm, 3.6M ohm 3.9 ohm, 39 ohm, 390 ohm, 3.9k ohm, 39k ohm, 390k ohm, 3.9M ohm 4.3 ohm, 43 ohm, 430 ohm, 4.3k ohm, 43K ohm, 430K ohm, 4.3M ohm 4.7 ohm, 47 ohm, 470 ohm, 4.7k ohm, 47k ohm, 470k ohm, 4.7M ohm 5.1 ohm, 51 ohm, 510 ohm, 5.1k ohm, 51k ohm, 510k ohm, 5.1M ohm 5.6 ohm, 56 ohm, 560 ohm, 5.6k ohm, 56k ohm, 560k ohm, 5.6M ohm 6.2 ohm, 62 ohm, 620 ohm, 6.2k ohm, 62K ohm, 620K ohm, 6.2M ohm 6.8 ohm, 68 ohm, 680 ohm, 6.8k ohm, 68k ohm, 680k ohm, 6.8M ohm 7.5 ohm, 75 ohm, 750 ohm, 7.5k ohm, 75k ohm, 750k ohm, 7.5M ohm 8.2 ohm, 82 ohm, 820 ohm, 8.2k ohm, 82k ohm, 820k ohm, 8.2M ohm 9.1 ohm, 91 ohm, 910 ohm, 9.1k ohm, 91k ohm, 910k ohm, 9.1M ohm #generics #CommonPartsLibrary
jharwinbarrozo
1.5M
Ground
A common return path for electric current. Commonly known as ground.
jharwinbarrozo
20.5M
Terminal
An electrical connector acting as reusable interface to a conductor and creating a point where external circuits can be connected.
natarius
Net Portal
Wirelessly connects nets on schematic. Used to organize schematics and separate functional blocks. To wirelessly connect net portals, give them same designator. #portal
jharwinbarrozo
43.0M
RMCF0805JT47K0
General Purpose Thick Film Standard Power and High-Power Chip Resistor 47 kOhms ±5% 0.125W, 1/8W Chip Resistor 0805 (2012 Metric) Automotive AEC-Q200 Thick Film Features: - RMCF – standard power ratings - RMCP – high power ratings - Nickel barrier terminations standard - Power derating from 100% at 70ºC to zero at +155ºC - RoHS compliant, REACH compliant, and halogen free - AEC-Q200 compliant
jharwinbarrozo
1.2M
875105359001
10 µF 16 V Aluminum - Polymer Capacitors Radial, Can - SMD 30mOhm 2000 Hrs @ 105°C #commonpartslibrary #capacitor #aluminumpolymer #radialcan
jharwinbarrozo
1.2M
CTL1206FYW1T
Yellow 595nm LED Indication - Discrete 1.7V 1206 (3216 Metric)
jharwinbarrozo
1.1M
1070TR
Battery Holder (Open) Coin, 20.0mm 1 Cell SMD (SMT) Tab bate or batt #forLedBlink
jharwinbarrozo
700.5k

Project Name

Description

Through-hole 9V battery-powered 555 timer circuit that blinks a red LED about once per second through an on/off switch, designed for easy hand soldering.

Properties

Properties describe core aspects of the project.

Pricing & Availability

Distributor	Qty 1
Arrow	$0.68–$0.99
Digi-Key	$6.42–$6.91
HQonline	$0.33
LCSC	$3.39
Mouser	$7.40
TME	$1.71
Verical	$8.10–$8.54

Controls

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