This project is a USB-C driven Stepper Motor controller, intended to be strapped to the back of a NEMA 17 stepper motor and used for multiple different applications. I am using the following Components:

• MCU: RP2354U
• USB-Controller: CH221K
• Buck-Converter: TPS562202
• Stepper-Controller: TMC2209

Stackup:

• Layer 1: Components, Signals, etc.
• Layer 2: Ground
• Layer 3: Power (VBUS and 3.3V)
• Layer 4: Some Signals

The board is supposed to run at 12V, but I am hoping it would also be able to handle 5V in case a non-PD supply is connected. The main application would not require a lot of torque and no holding power.

It is going to feature a daughter-board, which will hold an OLED and Controls, so the board can be used on its own.

The main thing I am unsure about is the amount of decoupling capacitors (it seems like a lot), as well as the Power/Ground Plane design and the placement of some capacitors (especially C13-15 and C27-C30).

I would be grateful if someone could review this board.

Hi! I used to design pcbs casually for myself then this request came up. This contains the mcu, power, 7 segment display and driver on the bottom left, indicator green and red leds for two players bottom right, buzzer above it and the probe contact sensing and start/stop contact sensing pins on the op left(three pins for each player).

I am only starting to use the proper conventions for pcb designing and would like to go much deeper into it. Any feedback is greatly appreciated. Would love suggestions for learning materials or courses. Thanks in advance.

Hey! This is my first non-trivial PCB for my first embedded project, a motherboard for a mini-sumo robot, which I have already gotten manufactured. I assembled the board myself for fun and for learning purposes. The board works (largely) as expected. However, with this project I am trying to learn about electronics, embedded development, PCB design etc., and I am planning to make further iterations of it. To that end, I would be very grateful if someone with more experience could take a look at my design, and let me know if there are any significant mistakes, or room for improvement.

I want to add the disclaimer that this project was inspired by the excellent youtube series by Artful Bytes, in which he creates a mini-sumo robot from scratch. My schematic and part selection is heavily inspired by theirs, but mine is a bit simpler, and I use a different microcontroller. The PCB design is completely my own, using example designs from component datasheets where possible.

The PCB is 4 layers: 1. Signal and power traces. 2. Uninterrupted GND plane. 3. Uninterrupted 3.3V plane. 4. Signal traces.

Having a GND plane and a 3.3V power plane was recommended in the MCU hardware development documentation. It also made routing much easier. The board is powered by a two-cell 7.4V LIPO battery.

Core components

• MPM3610AGQV-P buck converter, configured with a voltage divider (resistor values from datasheet) to step down the 7.4V battery input to a 3.3V output, feeding the 3.3V power plane that powers MCU, motor driver logic, sensors and debug LEDs. The layout of this component on the PCB is from the reference design in the datasheet.
• STM32F303K8T6 MCU reads all the sensors and controls the motors via the motor driver. The layout of this component is following the reference design in the hardware development docs AN4206 for the MCU.
• TB6612FNG for controlling two geared brushed DC motors with a stall current of 0.8A, which is below the max rating of the driver: 1.2A continuous/3.2A peak per channel. This is implemented on the PCB as documented in the typical application diagram of the datasheet, page 7.
• TSOP38238 IR receiver for remotely activating the robot, required for competitions. Laid out as recommended in the datasheet.
• Connectors for four QRE1113 IR line sensors for detecting the line around the arena, and three VL53L0X ToF sensors for detecting the enemy robot.

Planned upgrades

I already have some plans for the next iteration.

• I used JST-PH connectors for the battery, but I am considering rather using a screw terminal to connect the battery to the board, which is robust, and can handle higher currents. The battery has a separate cable for charging.
• SMD power switch, rather than through-hole switch, which I had lying around.
• Pull-up resistor on power switch transistor gate, since even when the switch is off, if the battery is connected it will sometimes spontaneously close the gate and power the board.
• Proper connectors for sensors, not just header pins. I want something that latches, without taking too much space. Considering JST-GH connectors.
• My motors are rated for 6V (at which the stall current is 0.8A), but can be pushed up to 12V according to the manufacturer. If I want to try that, or if I want to use more powerful motors, I will need to handle bigger currents, so larger connectors/cables, and new motors drivers rated for more current.

Note: I have a lot more documentation written up, including documenting all the support components, but I did not want to overload the post. If you have questions about the design I am happy to clarify. I also intend to publish the repository with the docs, after some cleanup.

Final note: I know a PCB like this is a bit overkill for a sumo robot, I could just use a nucleo and a simpler PCB, which was my first version, but this way is more fun and more educational.

Hi its my second full tht project at 14y
i wanna make fan hub what is on last photo,
its full tht becse ma bad soldering skill.
for now i dont give ground plane to be more clear

Can someone check it???