This project is focused on designing a highly efficient PCB for a switching power supply using a robust selection of electronic components. Our design leverages a flyback topology featuring a ferrite transformer (options EE25 or EE33), a PWM integrated circuit (TL494, SG3525, or UC3842), and a power MOSFET (IRF840 or a similar alternative) for effective high-voltage switching. Fast and reliable rectification is ensured by using a Schottky diode (MBR20100 or FR107) along with a rectifier bridge built from four 1N4007 diodes or a dedicated 4A bridge. Key stabilization and regulation components include the TL431 reference regulator and a Zener diode for precise voltage control in critical areas. For input and output filtering, the design incorporates electrolytic capacitors (470 µF, 25 V for output and 400 V, 100 µF for input) and ceramic capacitors (ranging from 1 nF to 100 nF) to limit high-frequency noise. Additional safety and operational features are provided by an NTC (soft-start thermistor) to prevent current spikes, various resistors (from 1 Ω to 100kΩ), an optocoupler (PC817) for signal isolation, a switch, and a protection fuse. Before moving forward with a finalized PCB layout and schematic details, we need to clarify a few design choices: 1. Transformer Choice: Would you prefer using the EE25 or the EE33 ferrite transformer variant as the heart of the switching power supply design? This detailed approach ensures that the power supply not only meets rigorous performance and safety standards but also supports a reliable and scalable solution for various electronic applications. #PCBDesign #SwitchingPowerSupply #Electronics #SMPS #PowerElectronics #FlybackConverter #CircuitDesign #ElectronicsComponents

R2 changes: -Moving to Letter Modules for ease of design -Adding ESP32 for WiFi On/Off and intensity control -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

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.

IMPORTANT NOTICE: Hey, I opened editing permissions and this doc is broken, see the frozen version here: https://www.flux.ai/markwuflux/on-air-markwu2001-remix-r1-backup-freeze-0b49 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.

R2 changes: -Moving to Letter Modules for ease of design -Adding ESP32 for WiFi On/Off and intensity control -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

Modified by markwu2001: - Adjustable Brightness, - 85-90% Drive Efficiency - <5W Operation (Can use 5V 1A Plug) 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.

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.

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.

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.

R2 changes: -Moving to Letter Modules for ease of design -Adding ESP32 for WiFi On/Off and intensity control -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

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.

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.