1/30/2026 2 PM - Research

I spent some time looking into what kind of features people usually add to Flipper Zero accessories. It was interesting to see that the ones people really like aren’t just random gadgets, they actually make the Flipper more useful in ways it couldn’t do on its own.

From what I found, Wi‑Fi connectivity keeps coming up as the top feature. Makes sense, since it opens up all kinds of possibilities like scanning networks, capturing packets, or just doing more wireless stuff. Seeing that helped me figure out what I wanted for my own accessory.

For my project, I decided to go with Wi‑Fi because it seemed genuinely useful and would give me more options to experiment. On top of that, I chose an IR blaster for my own purposes, kind of like giving the Flipper a little extra range and flexibility with infrared stuff that it couldn’t do as well before.

1/30/2026 10 PM - Created the Schematics

After doing a fair bit of research, I honestly thought this stage would be pretty smooth, but I ran straight into a massive wall and a much steeper learning curve than I was expecting.

The WiFi board felt a lot like making my dev board, just with different components and a whole new stack of datasheets to work through. The MCU being from the same company as the one on my dev board helped a lot, since the layout and documentation felt familiar and definitely sped things up. Even so, there was just so much going on that it became really time-consuming. I’d change one thing, then realise that a bunch of other parts depended on it and needed changing too. Every time I thought I was basically finished, something else popped up. Right at the end, the DRC errors hit, which took longer than I expected to track down and fix, and really dragged out what felt like the 'final' stage.

The IR blaster was a completely different kind of challenge. Even though it used way fewer parts and steps, it was honestly more confusing to wrap my head around. I kept running into conflicting advice about resistor values, whether a MOSFET or a transistor made more sense, if the LEDs should be in series or not, and whether using a 5V rail was better than 3.3V. I ended up doing the maths myself to work out that 5V actually made sense, which was frustrating at the time but pretty satisfying once it clicked. Compared to the WiFi board, there were hardly any DRC errors, probably just because the circuit was so much simpler overall.

I also had to make a few key design decisions along the way, mostly balancing capability with safety and future flexibility.

For the IR blaster, I ended up using seven IR LEDs, arranged as three pairs in series and one standalone LED, which was mainly a compromise between output power and practicality on a 5 V rail. Running LEDs in series helped keep the current more controlled and efficient, while the extra standalone LED let me push a bit more output without overcomplicating the layout. I chose to use a MOSFET rather than a transistor because it made more sense for switching higher pulsed currents efficiently while keeping the control side isolated from the load. That way, the Flipper only ever sees a clean logic-level signal on the gate, which felt much safer than risking current flowing directly through a GPIO pin.

For the WiFi board, I didn’t need an especially powerful MCU, so I chose the ESP32-S2-WROVER-N4R2, which felt like a good middle ground: powerful enough to handle WiFi and any expected tasks, but not unnecessarily complex. I deliberately left several IO pins free so the board could be expanded or repurposed later, rather than being locked into a single use. I also included a JTAG interface, a UART, and dedicated boot and reset buttons, mainly to make debugging and development easier and less frustrating if something goes wrong.

Across both boards, the most important consideration was making sure the Flipper stays protected. I was careful to design things so that, even in the case of a wiring mistake or electrical fault, the Flipper’s GPIO pins wouldn’t be exposed to unsafe voltages or currents. Using proper isolation through components like MOSFETs, limiting current where needed, and avoiding direct power paths back into the Flipper helped give me confidence that the designs wouldn’t risk damaging the device they’re meant to extend.

IR Blaster:

Wifi Module:

** Note: The large X's through a couple of the pin headers on the Wifi module signify DNP (Do Not Populate), that is because, when designing the PCB I don't want pin's soldered into header, I'd rather just leave the holes.

2/1/2026 4 PM - Footprints

This step took a bit longer than I expected. I hadn’t really looked into the specific parts yet, so I ended up figuring things out as I went. In past projects I usually spent more time planning first, but this time I kind of jumped straight into the schematic. I did some research beforehand, but there wasn’t much structure, which definitely slowed me down.

A little look at the Wifi module footprints:

2/1/2026 9 PM - Placed PCB components

I'm almost embarrassed to make this log, but I spend ages placing the components for the PCB. I wanted to make this board really neat since it had (hoped for it) to be pretty small. And in this process of optimising I was back and forwards with the schematic, looking at which parts went with which, and where the pin was for it on the MCU. I also tried to concentrate alot of the parts towards the middle of the board, I'm not 100% sure why but it just feels better.

2/2/2026 6 PM - Routed the Wifi Board PCB

With this board, I tried a few new things while also repeating techniques I’d used before and found reliable. Routing was the biggest step and took the most time, but making the board 4 layers helped a lot. Using the 2nd layer for +3V3 and the 3rd layer for GND made the ratsnest much easier to deal with, since many connections only needed a short trace and a single via instead of complex routing on one layer.

I also made the power routes wider than normal signal traces, as power lines carry more current and benefit from lower resistance and better noise performance, especially with an MCU and Wi-Fi on the board. Since there was enough space, widening them should help improve reliability without any real downside.

After finishing the main routing, I added stitching vias to better tie the ground planes together and then carefully checked the DRC multiple times to catch any remaining issues before finalising the board.

I'd also say that I spent a decent bit of time making sure the board looked nice. Out of all of my projects, this one by far looks the cleanest.

2/2/2026 7 PM - Routed the IR Blaster

The main thing I was focused on here was making sure the IR LEDs were in an optimal setup. I did a bit of quick research and found that as long as the LEDs are close together it’s fine, but the actual pulsing is what really matters for getting a good range.

With that in mind, I placed the components and routed everything. Once that was done, I threw down a simple GND fill on both the top and bottom layers.

The other change I made at the end was flipping the orientation of the IR LEDs. At first, I had them on the front side, but with the Flipper’s IO pins, that would mean the LEDs face the user. For better efficiency, I moved them to the back so they’re already pointing in the right direction when someone’s using it.

2/2/2026 8 PM - Parts

The last step before sending this project off for review is to lock in all the parts and give everything a good sanity check, making sure they all actually fit the footprints on the board and aren’t going to cause me any headaches later. I also want to make sure I’m not overspending, so I’m going through the BOM with a fine-tooth comb to see where I can shave a money without compromising functionality. Picking parts is always a balancing act because sometimes it’s obvious what to grab, but other times it’s a bit more fiddly.

There are a couple of costs I’m just going to cop on the chin. The MCU isn’t in stock right now, so I’ll have to buy it myself when it comes back, and the IR LEDs are in the same boat. Ideally, I’d like to source everything from one supplier to save on shipping and keep things simple, but availability trumps convenience here. Some of the smaller components, like the MOSFETs or the small TVS diodes, required me to compare datasheets carefully to make sure they meet the voltage and current requirements but also fit the tiny SMD footprints I’ve laid out.

Overall, this last step was all about making sure I haven’t missed anything obvious and that the project is all good to hopefully get approved.

2/3/2026 - Note for Reviewer

The reason I chose to create an IR blaster module was because the IR transmitter on my custom Flipper (which I hope to make) only has one IR LED and thus exceedingly poor range. So that sparked my want to create a much larger range IR emitter that can be easily attached to my Flipper.

I hope that makes sense. If you want to see my custom Flipper Project, it can been seen here: https://github.com/aaakum4/Sorta-Flipper-Zero
https://blueprint.hackclub.com/projects/7192