5 open source boards using the 4N28
Real designs built with the 4N28, from public GitHub projects: a quick way to see how others power, decouple and connect it. Each board comes with its KiCad files, full parts list and a render — and you can simulate its firmware on HardLabs.
ESP8266Cc pcbRedo
lagunter145
146.1 × 101.6 mm86 parts2LNo license2
AVR/ArduinoInefficient coil gun
jamesbrayy
440 × 196 mm151 parts2LMIT1
ESP8266Cc pcb
145.2 × 105.1 mm83 parts2LNo license2
Half bridge
profdc9
96.5 × 98 mm78 parts2LNo license56
Half bridge
iduwhux
96.5 × 98 mm75 parts2LNo license1
The 4N28 in open source designs
The gallery holds 5 open source boards using the 4N28 from 4 GitHub repositories; a typical one measures about 145.2 × 101.6 mm and carries around 83 components.
100% are two-layer designs, the rest use four layers or more, and 20% carry an open source license.
The most starred is Half bridge by profdc9.
Parts used alongside the 4N28
Microcontrollers on boards using the 4N28
What boards using the 4N28 are built for
4N28: common questions
Where can I find a 4N28 reference design?
Each of the 5 boards on this page is a real design using the 4N28. Open one to see how it is wired up, with the full BOM, a render of the layout and links to its KiCad files.
What parts are used alongside the 4N28?
The 40106, LM339, LM7815_TO220 and tc4420 appear in the most repositories here.
Which microcontrollers do boards using the 4N28 use?
Most are built on ESP8266 (2) and AVR/Arduino (1).
How big is a typical board using the 4N28?
The median is 145.2 × 101.6 mm, and 100% are two-layer designs.
What is the most popular open source board using the 4N28?
By GitHub stars, Half bridge by profdc9, with 56 stars.
Can I simulate one of these boards using the 4N28 before building it?
Yes. HardLabs turns a board's netlist and BOM into a working simulation, so you can boot and test firmware against it with no hardware on your desk.