Description
In this video, we are scaling up from small electronics to build a massive, custom 12-inch 4-digit 7-segment display panel! This heavy-duty display is perfect for outdoor clocks, scoreboards, and industrial counters. We break down how to design a custom driver board using an ESP8266 Wi-Fi microcontroller, daisy-chained 74HC595 shift registers, and ULN2003 Darlington transistor arrays to solve the high-voltage and high-current challenges of giant LEDs. You will also see how I prototyped the initial test sample and crafted custom plexiglass enclosures for each individual digit to make it weather-resistant and professional.
Key Formula Used (Ohm's Law):
Resistor = (Supply Voltage - LED Series Drop - ULN2003 Drop) / Desired Current
R = (12V - 8.0V - 1.1V) / 0.02A = 145 Ohms (Used 150 Ohm standard resistors)
If you enjoyed the video, please drop a LIKE, leave a comment if you have questions about the wiring, and SUBSCRIBE for more advanced DIY electronics projects!
Chapters:
0:00 - Introduction & Project Reveal
0:42 - The Hardware Challenge (Why we need Transistors)
1:28 - Multiplexing vs Shift Registers (74HC595 Explained)
2:00 - Exact Electrical Math & Resistor Calculations
2:45 - Custom Plexiglass Enclosures & Final Demo
HARDWARE USED IN THIS VIDEO:
• ESP8266 NodeMCU https://s.click.aliexpress.com/e/_c4e5t0Dn
• 74HC595 https://s.click.aliexpress.com/e/_c3kHHFRf
• ULN2003A https://s.click.aliexpress.com/e/_c3einxO9
• 12" LED 7 Segments https://s.click.aliexpress.com/e/_c338YGNn
• 12V Power Supply https://s.click.aliexpress.com/e/_c2IvpAC5
Useful Tools
electronic tool kit https://s.click.aliexpress.com/e/_dXrXRvq
Hardware tool kit https://s.click.aliexpress.com/e/_dSI86ek
Desktop oscilloscope https://s.click.aliexpress.com/e/_d8dX3vA
hand held oscilloscope https://s.click.aliexpress.com/e/_dXjzqsg
cordless drill + screw driver https://s.click.aliexpress.com/e/_d9nlgXq
power supply https://s.click.aliexpress.com/e/_dVMBg7O
soldering station https://s.click.aliexpress.com/e/_dXUJfBE
Drill press https://s.click.aliexpress.com/e/_d6GdtsG
3d printer https://www.aliexpress.com/item/33009066709.html
CNC machine https://s.click.aliexpress.com/e/_d7bmldW
My Channels:
KIYANI' KI LAB https://www.youtube.com/channel/UCCvpp9RUp-dQY3YDwki-ytQ
KIYANI TECH https://www.youtube.com/channel/UCH-GoRUL47hLHOCHNSG8tbg
Instagram: https://www.instagram.com/kiyani676/
fecebook: https://www.facebook.com/Kiyanis-Lab-1520512291502452/
Previous videos:
https://www.youtube.com/watch?v=2DCVTFS8w0w&list=PLvlwETz0FTvuwDSpe2E-pmTe8BSC9xkRq
https://www.youtube.com/watch?v=Y2gYSHQ6imQ&list=PLvlwETz0FTvsESxm5PWjcrWSVxP_krMM5
#DIYElectronics #ESP8266 #7SegmentDisplay #ArduinoProject #CustomLED #74HC595 #ULN2003 #MakerMovement