Question about custom VNH5019 board

Support Motor controllers/drivers and motors
1

Hello,
I want to base my custom PCB project off of the pololu VNH5019 dual h-bridge boards. I have a couple of questions concerning the layout I currently have:

1278×584 1.03 MB

The MOSFETs I routed with are standard SOT-23 packages, and will generally not be able to conduct more than 2A of current. There are the ones used as reverse-battery protection, in the pololu schematic.
I would like to know 2 things:

  1. Will these smaller MOSFETs (shown in pink rctangles) work? I figure they are only useful for reverse-voltage protection. If they will not suit this purpose, what type of MOSFET would you recommend?
  2. Is it possible to solder the motor drivers without a reflow oven? I have a hot-air gun, best case scenario. I’m not sure how to proceed with the heat slugs underneath the IC.

Thanks!
Paulo

2

Hello, Paulo.

The MOSFETs used for reverse voltage protection should be able to handle the current drawn by the motor driver. The VNH5019 driver can deliver up to 30A, so you will probably want to use a MOSFET that can handle at least that.

It might be possible to solder the motor driver using a hot-air gun. There are also many DIY solutions for soldering surface mount devices, such as using a skillet or toaster oven, that you might look into.

- Jeremy