I'm still waiting for the v.02 boards to arrived, so in the meantime I continued over-engineering the v.03 board and ended up with this:
![](https://cdn.hackaday.io/images/2407931619665264602.png)
In this iteration, I liberally added thermal vias under every component which could potentially get hot with 2~3A of current going through it. I also added more silkscreen labels to clearly identify things, and switched from 6-pin to 8-pin JST header. This adds an extra GND pin to make it easier to wire 5V to one device, and 3.3V to another device. I also decided to break out the DE pin so it's possible to control that pin through an MCU as well.
![](https://cdn.hackaday.io/images/1651691619666582916.png)
The DIP switch allows for manual configuration of the RS485
operating mode (receiver/driver/off), and there's a 3-pin header which
can connect VIN to RJ45. I initially wanted to use a high-current rocker
switch, but it adds a lot of bulk and cost to the module, so I opted
for a riskier 3-pin header with scary warning labels.
![](https://cdn.hackaday.io/images/7262261619666546833.png)
The important thing is to avoid touching those headers while the board is powered. That's common sense, but hey...
Anyways, since this is more of a development/hacker board, people are free to wire things as they wish (ex: skip soldering the 3-pin header, use an 8-pin header instead of the JST connector, etc).
The 3.3V LDO was initially user-selectable, but I decided to opt for an SMD SOT-223 LDO which is limited to 1A but should be fine for powering a small MCU like an Arduino Pro Mini.
For now I'll keep waiting for v.02 before making further changes to v.03.
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