12V IN ↓ (polyfuse 2–3A) → (reverse-polarity diode or ideal diode) → (SMBJ13A TVS) ↓ Buck 12V → 5V @ 4–5A (synchronous buck, e.g., MP1584/MP2307) ↓ 5V bus → bulk caps (2×1000 µF) → WS2812B matrix ↘ (optional) 5V → dev board VIN (see USB backfeed note) Dev board 3.3V: from its onboard regulator Data: ESP32 GPIO → 74AHCT125 (level shift to 5V) → 33–100 Ω → LED#1 DIN

LEDs

• 80 pcs WS2812B-3535 RGB LED
  • Package: 3535 (3.5 × 3.5 mm, SMD)
  • Part Example: Worldsemi WS2812B-3535 (or equivalent SK6812 mini-E)
  • Notes: Pick tape-and-reel if you plan to reflow; hand-solderable with hot air + flux.

ask GPT

Controller

• 1 pc ESP32 DevKitC (or ESP32-WROOM-32 module + headers)
  • Why: easy programming over USB, runs FastLED/NeoPixel easily.
  • Alternative: Arduino Nano Every (if you want pure 5 V).

Esp32 shoppee?

Level Shifter (only if MCU is 3.3 V like ESP32)

• 1 pc 74AHCT125N or SN74HCT245N
  • Converts 3.3 V data → 5 V, reliable at 800 kHz.
  • Put close to the first LED DIN.

Power Input & Regulation

• 1 pc DC barrel jack (2.1 mm ID, 5.5 mm OD, through-hole) or USB-C power-only module
• 1 pc 5 V / 5 A external PSU brick (regulated)
• 2 pcs Electrolytic capacitor, 1000 µF / 10 V (power entry + mid-panel)
• ~20 pcs 0.1 µF ceramic capacitor (0603/0805), one per 2–3 LEDs (ideal: 1 per LED if space/cost okay)

Uhm 12V?? for lower amperage, design power net

Protection & Stability

• 1 pc Series resistor, 33–100 Ω (0402–0805) in the data line (at DIN of first LED)
• 1 pc (optional) TVS diode SMBJ5.0A between +5 V and GND (for surge/spikes)
• 1 pc (optional) Schottky diode (e.g., SS14) for reverse polarity protection