High-level recreation of the ThirstIQ Cap wiring diagram using an ESP32-WROOM-32 with AMS1117-3.3 regulated battery input, inline ON/OFF switch, four touch input headers on IO32/IO33/IO25/IO26, shared I2C OLED and RTC on IO21/IO22, UART debug/programming header on TXD0/RXD0, BOOT and RESET pushbuttons on IO0 and EN, buzzer on IO4, common 3V3/GND distribution, and PCB preparation for a 160 mm x 100 mm 4-layer layout. Layout intent includes clean 3.3 V power distribution, local decoupling for regulator and ESP32, accessible external headers/buttons, short clean BOOT/EN traces, shared I2C routing, touch-signal separation from noisy power and buzzer traces, and ESP32 antenna keepout.

R2 w Thread changes: -Moving to Letter Modules for ease of design -Adding MGM210L for Matter on Thread On/Off and intensity control -Shifted A and R letters closer to fix Kerning -Optional: Add unpopulated AA Battery Holder for battery option R1 changes: -Changed LED part to Red LEDs -adjusted resistor value of buck converter -Changed source for USB-C Connector -Removed exposed soldermask on buck converter with negative soldermask expansion -Order with black soldermask Modified by markwu2001: - Adjustable Brightness, - 85-90% Drive Efficiency - <5W Operation (Can use 5V 1A Plug) This project can be purchased from LCSC Original Description: Daddy's second circuit board. A sign to let my wife know when I'm on a call. Activates with a slide switch and is powered by USB-C. #template #arduino-matter

Constellation PCB - Meant to blink LEDs representing the constellation Cassiopeia - On/off switch for controlling the LEDs and switches to control the colors of the LEDs

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.

Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, through-hole passives, and a PP3 battery holder.