cross-posted from: https://sh.itjust.works/post/13637559

Hello everyone, I need some advice.

I am making custom PCBs for a project of mine. It's basically for a little remotely controlled robot using little DC motors. I chose the Seeed Studio XIAO ESP32C3 as the uC since it has inbuilt wifi/bt, 3.3V regulator that I can use to power the motors (can source up to 700mA) and lipo charging management (the robots will run on battery). As you can see from here, the microcontroller is surface mounted and the pads for the battery are on the bottom layer. Same story goes for the thermal pad of the microcontroller and the thermal pad of the motor driver (datasheet). I have worked with SMD components in the past and can solder them by hand, but I have never worked with SMD components that have thermal pads on the bottom layer. My question is: how to manage (route?) them? My PCB is 2-layer and I was planning on having both layers filled with a ground plane. Do I just connect thermal pads to the ground plane and call it a day? Wouldn't that make the components hard to solder with hot air? Do I make an isolated polygon that only acts as a thermal pad?

Speaking of soldering is even hot air the way to go in this case? My PCB has components on both sides, and I was planning on ordering stencils together with the boards and using solder paste, placing the components and then using hot air to solder the components in place. I thought a hot plate would be better but I don't have access to one and I don't know how that works with components on both sides.

I attached some photos of the PCB in Kicad, and here's the git repo. If it is of any help, I'm planning of having them manifactured by JLCPCB. It is also my first time using KiCad, so go easy on me :)

Thanks!

What I ended up doing was making my own battery by using 2x18650 connected in series to get the 6V the camcorder needed and a buck converter and worked like charm. I didn't want to end up buying already "built" batteries from a seller in Aliexpress.

Here I wrote a little more about it with images. https://0x00.cl/blog/2023/making-my-own-battery/

Hello,

I have an old sony camera that has an old Ni-Cd battery (6V 3000mAh) and of course now the charge doesn't last long. They do sell "new" batteries for it but its from Aliexpress and I don't want to rely on 1 not so reputable seller incase I need a new one. So I wanted to repair it and "upgrade" it myself, but im no electrician or anything I just like to tinker with electronics so I had a few questions.

The battery and camera only have 2 connections, positive (+) and negative (-). I saw on aliexpress that they sell a 6V 4200mAh battery pack, which is made of 5xAA (1.2V) Ni-Mh rechargable batteries. Would it be as simple as that, if I connect the positive and negative to the corresponding ones on the old camera it should work?

Is there anything else I should take into consideration?

EDIT: The camera Is a Sony CCD-TR403 EDIT2: or would it be better to build my own battery pack with 18650

Planning on building a flight stick for a space sim. I understand some basics and I've messed around with an Arduino and a breadboard.

In the planning stages now. Should I measure the axis and rotations on the sim stick with hall effect sensors? Is there a more precise alternative?

I would also like to control the tension on the stick with brushless dc motors like done in this project https://youtu.be/ip641WmY4pA and I think the hall effect shouldn't get interference from the motors. Hopefully.