LED Blinking Circuit Design
Worked for 4 mins 6 sec
Created 2 project docs
Project Specification
Hand-solderable 9V battery powered red LED blinker using a DIP-8 NE555 timer in astable mode. The LED blinks approximately once per second a...
View docBoard Bring-Up Plan
Inspect solder joints, especially BT1, SW1, U1, C1 polarity, D1 polarity, and the axial resistors. Confirm C1 positive lead is connected to ...
View docBuilt the schematic for a hand-solderable 9V NE555 red LED blinker and renamed the project 1 Hz 555 LED Blinker. It uses a 9V battery holder, SPST slide switch, DIP-8 NE555, through-hole LED, axial resistors, and leaded capacitors; ERC/review checks show no open warnings or errors.
Open items:
- PCB placement/routing has not been done yet.
- Blink rate is nominally ~0.99 Hz; electrolytic capacitor tolerance will shift the exact timing.
Docs created:
Suggested next steps:
- Place the through-hole parts on a simple PCB.
- Route the board.
- Add silkscreen labels for battery polarity, switch ON direction, LED polarity, and 555 orientation.
Place route review
Place the PCB
Route the board
Add silkscreen labels
Run layout checks
Refine this doc
Ask about this doc
Project Specification
Overview
Hand-solderable 9V battery powered red LED blinker using a DIP-8 NE555 timer in astable mode. The LED blinks approximately once per second and power is controlled with a through-hole SPST slide switch.
Requirements
- Power source: 9V PP3/block battery.
- User control: on/off switch in series with battery positive.
- Output: red LED blink indicator.
- Blink rate: approximately 1 Hz / once per second.
- Assembly: prioritize through-hole, hand-solderable components.
Circuit Topology
- BT1: BH9VPC 9V battery holder.
- SW1: AS11CH SPST through-hole slide switch.
- U1: NE555P DIP-8 timer powered from switched 9V.
- R1 = 10 kΩ from V9_SW to DISCH.
- R2 = 68 kΩ from DISCH to TRIG/THRES.
- C1 = 10 µF from TRIG/THRES to GND, positive on timing node.
- C2 = 0.1 µF from V9_SW to GND near U1.
- C3 = 0.01 µF from CONT to GND.
- R3 = 680 Ω in series with red LED D1 from U1 OUT to GND.
Timing Estimate
For a 555 astable:
- t_high = 0.693 × (R1 + R2) × C1
- t_low = 0.693 × R2 × C1
- period = 0.693 × (R1 + 2R2) × C1
With R1 = 10 kΩ, R2 = 68 kΩ, C1 = 10 µF:
- t_high ≈ 0.54 s
- t_low ≈ 0.47 s
- period ≈ 1.01 s
- frequency ≈ 0.99 Hz
Electrolytic tolerance will affect the exact blink rate, but it should visibly blink about once per second.
Validation Criteria
- U1 VCC and RESET tied to switched 9V.
- U1 GND tied to battery negative.
- TRIG and THRES tied together at the C1 timing node.
- DISCH connected between R1 and R2.
- CONT bypassed to GND with 10 nF.
- Output drives red LED through a current-limiting resistor.
- ERC has no open errors/warnings for the checked schematic rules.
Overview
Requirements
Circuit Topology
Timing Estimate
Validation Criteria
