Hi,
I finished a small vehicle project recently, where space and power consumption were important constraints. I was using an ATTiny85 and an L293D h-bridge to control one motor. My initial intention was to run everything from a 3 AAA battery pack, however the h-bridge didn't find that sufficient. I would get many issues related to low voltage and therefore had to upgrade to a 4 AA battery pack, when everything eventually ran smoothly. As a consequence, I also had to add a voltage regulator to the whole design, since the microcontroller doesn't like the ~6 V coming from the battery pack.
Long story sort, I did not appreciate I had to use much more space, however time was pressing so I used the L293D anyway.
I was reading here and there that the L293D is sort of antiquated and other chips should/can be used instead. However, I could not find a specific suggestion on which to use.
So, what do you think? Which IC would be able to drive a simple and small DC motor, at preferably low voltages (and currents) using let's say a small LiPo battery? (I am mentioning a LiPo battery, since my custom made h-bridge didn't have a problem driving a bigger DC motor with a tiny 250 mAh LiPo)
Oh it also has to be as affordable as the L293D.
Take a look at the motor drivers from Pololu. This one might work, but you do need to know the stall current of your motor (which it will momentarily draw every time it starts up).
jremington:
Take a look at the motor drivers from Pololu. This one might work, but you do need to know the stall current of your motor (which it will momentarily draw every time it starts up).
The one you suggested looks pretty neat. Why would I need to know the current? Isn't it enough to know that it won't peak for example over the maximum limit of the IC? (1.8A from what I read)
The IC will protect itself from overcurrent. If your motor draws much more than 1.8 amperes, it may start to run, then stop.
If you have a multimeter, try to measure the resistance between the motor terminals while turning the shaft slowly. The stall current is approximately the battery voltage divided by the lowest resistance value you measure.
jremington:
The IC will protect itself from overcurrent. If your motor draws much more than 1.8 amperes, it may start to run, then stop.
If you have a multimeter, try to measure the resistance between the motor terminals while turning the shaft slowly. The stall current is approximately the battery voltage divided by the lowest resistance value you measure.
OK, I don't think that will be a problem, thanks for the clarification!
@dave-in-nj from a first look it seems like it's too much for what I want to accomplish (will it work with non-stepper motors too?) but thanks for your input!
