Hi,
I'm not sure if this is the correct category for this, but...
I am having an issue with my L293D motor driver that causes the 12V DC gear motor I have to run at a much slower speed when connected to the driver. I am only running one motor off of the driver. The motor's no-load current draw is <=80ma (I am not applying a load) I have a 12V power supply (it actually supplies 17.5V, not sure if that's an issue) rated at 500ma that I am running it off of. When I run the motor on the motor driver at full speed it runs slowly and is very weak. If I connect it directly to the power supply, it runs much faster with more power. The voltage drop over the driver appears to be negligible (about 0.4 volts). I have connected the driver properly (I referenced 3 different tutorials).
The reason I am asking this is because the similar questions all seem to be referencing a significant voltage drop which is causing the motor to run slowly and mine does not appear to have any voltage drop but is still running slowly. I would greatly appreciate any help and I will provide more information if necessary.
What do you get when you measure the voltage across the motor while it is operating?
Please post a schematic. Written descriptions are always more ambiguous than a drawing. Hand drawn, photographed and posted is fine. Include all pin names/numbers, components, their part numbers and/or values and power supplies.
Please post your test code. Please read the forum guidelines to see how to properly post code and some information on making a good post.
Use the IDE autoformat tool (ctrl-t or Tools, Auto format) before posting code in a code block.
Yes. The L293D is quite old and inefficient. You can expect about 4V loss as heat if it is saturated. The motor power supply is almost certainly inadequate, as well.
Post a link to the product page or data sheet for your motor, and consider moving to modern MOSFET motor drivers, which are much more capable and efficient than the L293D. Pololu has the best selection.
The rated current for that motor is 600 mA, which means that the stall current is probably in the range of 3 to 6 Amperes. The motor draws the stall current every time it starts up.
You need a power supply and motor driver that can supply that current. This motor driver would probably work well.