H T M (A) A
MAS.863 | How to Make (Almost) Anything
0: Final Project
1: Project Management / Computer-Controlled Cutting
2: Electronics Production
3: 3D scanning / printing
4: Electronics Design
5: Computer-Controlled Machining
6: Embedded Programming
7: Molding and Casting
8: Input Devices
9: Output Devices
10: Machine Design
11:Interface and Application Programming
12: Networking and Communications
13: Wildcard
ABOUT

9: Output Devices

add an output device to a microcontroller board

Lots of things went wrong this week. I made Neil's DC motor board three times. For the first one I made, I put MOSFET N-channel instead of the 5V regulator. The MOSFET burned immediately when I connected power to the board. I thought I connected the power supply in the wrong direction and shortcircuited it somehow, as the 9V battery was also hot. In my frustration I tried to salvage the board using jumper cables to reconnect a new MOSFET. It was quite a piece of work.

A flying MOSFET.

But again, it immediately burned upon putting the power supply.

Reading through other people's websites I realized I made the mistake of putting the MOSFET where a 5V regulator is supposed to go. So I milled another board, used 5V regulator instead of the MOSFET on this one. Nothing burned when I connected power. Good. Loaded Neil's DC motor program on the board. It said it was successful. Great. I connected the DC motor. Nothing happened.

Because the programmer said it successfully loaded the program onto the board, I suspected that there was a problem in the downstream. The oscilloscope was showing that there was signal going to the output but the signals seemed to be not following a coherent pattern. The problem was with the H bridge. Looking again to other people's websites.. found out that I was supposed to connect LSS pin to the ground plane. (Link to the datasheet: A4952/A4953)

And finally, a happy motor.

The lack of knowledge in electronics is really taking toll on me. I tried reading the Art of Electronics but it was too dense and unfamiliar for me who had 0 experience in electronics to read through. I tried reading the student manual for the Art of Electronics. Little bit better. Then I started read Forrest Mims III's 'Getting Started in Electronics' by Jackie's suggestion - this book helped me visualize what is going on better. Still a little bit confused. I am reading Charles Platt's 'Make:Electronics' and it is finally helping me understand the basics of electronics. I have a long way to go, but at least for now I am making bits of progress here and there on un-blackboxing the machines I am using.