1/27/2026 11:30 AM - Made LED Routing

For my 84 keys, I made 84 LEDS. From previous experience, I will be doing it properly this time with a 5v logic shifter and the resistor at the start. With my previous build, the LEDS caused me lots of problems so I don't want to go through that again.

I added 4 decoupling caps too just in case.

While it is suggested to have one per LED, I don't want to solder all of them so hopefully this is enough.

1/27/2026 11:34 AM - Switch Matrix

Pretty standard switch matrix. I wanted to rename all the switches, but I realised that would take too long and I'm fine with leaving it as it is, so this is fine.

1/27/2026 1:21 PM - Power Management

I started with two Lipos, for double the capacity. This means I need two chargers. I chose to use two MCP73871s because they were cheap.

I had several different ideas for voltage regulating, from having one double buck-boost converter to two ldos, and I ended up with this plan:
I would have one ldo for 3v3 since it will not draw that much current. However, for the LEDS I want to have 5v, so I will need a boost converter for this. I chose the ncv517edr2g because it was the cheapest option on digikey.

I had to create a custom symbol for this.

1/27/2026 1:54 PM - Switch to Nrf board

After looking at how the nrf wires, I realised that this would be way to complex to be hand soldered. Instead, I chose the nRF52840 pro micro because of its low cost on aliexpress. This board came with a battery charging circuit which was even better, so I could remove some complexity. Unfortunately, this only has 21 gpio pins while i need 23, so i need some sort of extender.

This made the leds need to be run off of 3v3 too, which is unfortunate but unavoidable.

With that, the entire pcb has been finished.

1/27/2026 2 PM - Switch Placement

The switches and controller have been placed.

The board will be on a standoff so it does not collide with the switch and leds, and will be mounted underneath the pcb. Same mounting as my old keyboard, because it has proved to work and fit with the case.

1/27/2026 9 PM - Component Places

After putting on the leds, I found a much better place for the pro micro. Then I realised that I could add another usb c pin for charging, which would make this much smaller while still retaining capabilities.

Never mind! Turns out I can't add another usb c port, so I will have to charge this keyboard upside down... reminds me of the apple magic mouse lmao

I added the diodes, and now I need to start routing!

1/27/2026 10 PM - Routed the PCB in record time

It's kinda crazy how much I have improved in the past couple months. The first time I routed a pcb, it took me 6-7 hours and I had to do so many redos because of how messy it was. This time, I planned out component placement and it just came together so well.

1/28/2026 - Ground and Power Plane

I decided to remove the power traces with ground and power planes. This should be slightly better in terms of performance, and the pcb looks better too.