2/12/2026 11 AM - Planing

I have started multiple projects at once (CNC,Smart Hub). As im trying to rack as many projects and build hours for a 3D printer :). Anyways so My design ideas and specification of the watch is

Have a proper touch display
Look and feels like a commercially available display
Modifiable firmware
Have some "hacking" features
A MCU with WIFI and Bt.
Also looking forward to have a MCU with and Native HID for some features im planning.

According to these design ideas im going to be going with a esp32-s3 as of now as its power efficent as well. I also have to plan alot more. As well as using 4 layer board

2/12/2026 5:20 PM - Parts Selection and Importing Them

So I used a script I made which takes the LCSC part no and then will download the proper footprint and symbol library for it. This is way easier than downloading them individually. But still I had a lot of problems findings parts like the esp32 it self. I searched for the part no on lcsc just to see it was restricted behind JLC assembly. Good thing i'll be using it for this.

These are the lcsc no.s for my components

C7558093 C17356995 C2836813 C404328 C527464 C19190864 C2682616 C3229350 C28441 C892227 C556936 C145875 C70022

2/12/2026 5:58 PM - Starting Schematics

So now let's begin the core the project. The Schematics. So Im going to be starting with the chip itself.

We have to wire the pins to other components as well. But now lets have place-holder netlabels. Also I will have to put an Antenna to the LNA_IN pin. As there is no built-in antenna. I took some time to wire them.

2/12/2026 6:15 PM - Next is the battery and gauge schematics

To measure the battery percentage and other stuff we need this. I have went with the Max1..

This was a quick wiring as I have done this before in a different project as well.

2/12/2026 6:17 PM - Audio Schematics

I have decided on adding a adding a mic (MICI2SSPH0645) and magnetic buzzer / vibrator for feed backs.
I also found the symbol diagram from an old sketchy website but it was safe.

2/12/2026 6:47 PM - USB C wiring

The function of the USB C is to charge the watch, program the watch and other normal stuff people do with the USB C. So I have completed the schematics for USB , power paths and filtering. And most importantly to charge the lion battery.
(I also added a small led to indicate the power flow for debugging reasons as well)

2/13/2026 - RTC (Real Time Clock)

A watch without a proper RTC? Crazy right. We need a RTC module for this as well. Im going with the RV-3028-C7-32.768KHZ. (i dont know what im doing neither did some research w/ Ai). I had to look into the Data Sheet to wire this from an old website as there was none attached to the KiCad Symbol.

I also used a an symbol from Unexpected Maker which I think is a famous Youtuber.

2/15/2026 - Spent alot of time with schematics.

I have been doing the schematics while in school so I didn`t really journal it properly. But i noted the time taken.

[1st Hour]
Next thing is the actual screen. Who builds a smart watch without a display. I dont really have a proper display model in mind that im going to be using so I have used the generic 1x18 connector pin which Il assign a FFC connector footprint later (the display ribbon). I have do some research on FFC before actually designing the schematics. Its also going to be a touch display.

[Next 30 minutes]
Next thing I made is the haptic feedback. It will send out feedback and stuff. I got this idea when i tared down a old smartwatch to get an idea.

[Final 30 minutes]
Finally I have added the buttons that will be on the sides. Like to power on the watch. This was easy but i kind of messed up multiple times before getting a proper schematics.

Summary: I am almost done with the schematics. (infact im done I just have to add the solder pads)
The actual PCB design is going to be tricky like I have to fit everything into small compact space. As mentioned before I am going to be using 4 layer board.

2/16/2026 3:20 PM - Assigning Footprints time

This is the worst part of doing the PCB. It took me the most time. I had to go through parts individually. Find the proper footprints online. Checked sized. Looked for parts as small as possible. It was a headache staring at the white screen for like 2 hours straight. Atleast its over. Next is the PCB design which is the fun and tricky part too.

This journal is being written like 15 hours later. I assigned the footprints while in bed and after finishing I went directly to bed. It was like 11pm.

2/16/2026 3:51 PM - PCB Time :D

So I spent an hour on size fitting and plain fitting the PCB components. So I can route them next. I went went this sleek placement. I also got some ideas from Youtube videos regarding small PCBs footprint placements. Like shortcuts, tips and tricks.

This is what I have went with for now. The placement will mostly change when I route for better accuracy.

2/17/2026 - PCB Complete

[Hour 1]
I have routed half of the top layer. Did some place switching for better routing. Also had some values wrong in the schematics so I changed them.

[Hour 2]
Completed the top layer. Moving to the next layers. Did some routing in the bottom layer as well. Made sure differential pairs for USB. And buttons like RST , BOOT.

[Hour 3]
Completed the second layer and almost the bottom layer. Had to change positions again on the top layer so I had re route some of the top layer.

[Hour 4]
99% Finished PCB. All 4 layers are routed properly. Did some position changing so It could fit on a small case.

[Last 30 mins]
Added some silkscreen branding and like indicators for the LEDS. Also calculated some math for the watch case later. Also assigned some 3d models to the components