Hello, everyone! I am new to this forum, but am a big fan of the site.
I'd like to start off with a question. I am building my first robot, and have decided to use two power sources:
- A 9-volt battery, regulated down to 5 volts for the control electronics
- 5 1.2v rechargeable batteries (for a total of 6v) for use with the engines
My trouble comes with the motor driver (L293D). While it has two voltage inputs (logic and supply), the ground is, as far as I can tell, common.
I have tried to connect the ground of the 6-volt pack to the regulated 5-volt power, this caused three of the batteries in the pack to discharge.
How can I use different voltages like this? Thanks in advance for any help.