Work done
- Retrieved the required schematic/layout guidance and checked the project state.
- Created a complete 555 timer LED flasher schematic in the project, using U1 NE555P, D1 red LED, R1 330Ω, R2 10kΩ, R3 100kΩ, C1 10uF, C2 100nF, C3 10nF, and J1 5V/GND input.
- Wired U1 in astable mode: 5V/GND power, RESET tied high, DISCH/THRES/TRIG timing network, CONT bypassed, and OUT driving the LED through R1.
- Renamed the project to 555 LED Flasher and added Design Notes documenting the value choices and ~0.7 Hz blink-rate estimate.
- Verified the schematic and BOM/ERC review: no open ERROR/WARNING review issues were reported at the time checked.
Success criteria review
- ✅ Complete flashing LED schematic using a 555 astable circuit was created.
- ✅ Power, ground, timing, control-bypass, and LED output connections were established.
- ✅ ERC/BOM review returned no active ERROR/WARNING/OPEN issues at verification time.
- ⚠️ Basic PCB preparation was only partially reached: the layout exists, but I could not continue to resize/place/route due to execution limits.
Next steps
I can proceed to PCB layout when available: set a compact board size/2-layer stackup, optionally add mounting holes, place the connector at an edge, group the 555 timing components near U1, then route and run DRC/airwire checks.