Task: remote control a lot of hacked toy hamster to start, stop and light blue on command.
Given the number of hamsters to control (about 20) this was an opportunity to design my own Arduino based miniature microcontroller board.
- IR receiver
- H brigde motor driver for almost any motor voltage.
- 3x LED open drain drivers
- 7-30V power input w/battery monitoring
- a little prototyping area
[will add photo of schematics here]
I used Pad2Pad for the manufacturing and used their PCB design software which was realy easy to learn.
In future productions I will mostly use these cards to avoid extra cards, and reduce space and cost.
Design flaws found so far:
- Motor driver gates need pull downs to make sure they are all “off” when microcontroller outputs are three-stated.
- Motor drivers could with a slight change bee all galvanicaly isolated trough the optocouplers. This would be nice.
- The third LED output PWM colides with the IR-outputs timing so I have to choose between dimming LED3 or using IR input. This could be avoided by choosing another output pin for this driver.