I am a beginner in robotics. I am planning to drive a 12V DC motor from Raspberry Pi 2 B. I know Pi does not have that capacity to drive such a device, so I am using L293D motor driver to control the DC motor. However, the problem is the 12 V supply requirement of the DC motor.
I know I can invest and buy these high power Duracell (any other) batteries and plug them to the DC motor supply. But the drawback is, that these batteries are non-rechargeable and as a result I'll be in constant need of purchasing new ones. The rechargeable batteries are very expensive for me.
So, I found about about these Boost converters, that can convert 5V to any other higher voltage say, 12 V. XL6009 is the module I'm interested in buying. However, I wanted to know that is it recommended to use XL6009 regulators to drive 12 V DC motors?
The XL6009 module will be powered with 5V DC supply from a separate source.
Please suggest any other alternatives, if XL6009/boost regulators are not an ideal source of supply for DC motors.
XL6009 details can be found here – https://www.sunrom.com/p/step-up-dc-dc-based-on-xl6009
L293D details can be found here –http://www.ti.com/product/L293D
Motor details can be found here – https://www.amazon.in/NTL-National-Multipurpose-Brushed-Applications/dp/B01FW9IHN0/ref=sr_1_1?s=industrial&ie=UTF8&qid=1517932524&sr=1-1&keywords=12v+dc+motor&dpID=41YN%252B0n3FYL&preST=_SX342_QL70_&dpSrc=srch
Best Answer
5V boosted to 12V means 12V/5V= 2.4 times the current.
IE: If you are drawing 1A at the 12V output, you need 2.4A at the 5V input. And that's at 100% efficiency, which we all know is not possible. That boost module states an efficiency of about 94%, but I'd still expect less.
That boost module link states a 4A input max and that the inductor can handle 3A max. I can say from experiance with those very boost modules that 3A continuous will burn them out at room temperature without heatsinks and fans. I'd say 2A is a good limit.
You did not give any details about the motor other than it is "12V"...Your motor will have current spikes upon starting, which you may be able to get away with, as it won't be continuous.
However, the motor appears to be rated at 1.2A max. You need 2.4*1.2A= 2.88A on the 5V input. That's awfully close to the hard-limit of 3A. If we also consider the current spikes upon starting or 'power-breaking' (quickly reversing direction), the current will be higher still.
I would not feel comfortable with that boost converter for extended use. It would be less an issue if the motor were used at only partial capacity. If it is used lightly then you may be fine.
Regardless, I would recommend connecting a PTC (auto resetting fuse) inline with the input of the boost converter. They don't cost much.
PTF fuses can take a while to blow at 100-150% (seconds to minutes), so pick a rating of about 2A. That way, there is some form of protection against a stalled/"stuck" motor. They are thermal based, and will heat up (a lot) once they trip. In order for them to "reset", the current must be dropped.