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Have been reading many articles showing how to connect DC motors to the Raspberry Pi and of course a DC Motor Driver Chip/Board is needed to come between DC motors and the Raspberry Pi GPIO Pins to be able to control the motor.

In many diagrams, they show how to connect batteries pack using a breadboard and a DC Motor Driver Chip/Board hooked up on the breadboard.

And a DC Power 5V pin and a GROUND pin of the Raspberry Pi are also connected to the DC Motor Driver Chip/Board through the breadboard.

None of the diagrams show that the Raspberry Pi itself is connected to the power source through its own micro USB or USB port. And the Raspberry Pi needs max 5V power to start up. Not more than 5V.

I plan to use L293DNE Dual H-Bridge Motor Driver. My question is:

Besides controlling DC motors, is L293DNE Dual H-Bridge Motor Driver Chip/Board itself also a 5V voltage regulator/converter which can be used to power the Raspberry Pi up from AA batteries?

Because it does not make sense to me if DC motors use a batteries pack and the Raspberry Pi uses another separate power source?

  • Do you mean the L293D? It is a chip and provides no voltage regulation. If you are thinking of a similarly named motor driver board you will have to provide a link to its specs to get a useful comment. – joan Oct 22 at 16:06
  • To be specific, it is L293DNE which is on the chip itself. A website uses LD293D with extra D by mistake, I guess. – O Connor Oct 23 at 7:20
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You can use the L293D for driving motor. It is possible to use it with L293D IC. you must provide the IC power from external source. Using raspberry pi and L293D with a same adapter is not recommended

  • I believe Raspberry Pi can provide enough power from its micro USB power source through to the motors. Is it possible to power the motors using power source from Raspberry Pi micro USB with a DC motor driver in between without using two separate power suppliers? – O Connor Oct 23 at 7:28
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The L293DNE is a chip and provides no voltage regulation. It requires two voltage INPUTS. One at 5V (Vcc1) for its internal logic and one at the motor voltage (Vcc2) you plan to use.

Of course you could power the Pi from the same source you plan to provide 5V to the chip.

  • That means I need an extra 5V voltage regulator to connect between the Raspberry Pi and the AA batteries pack? – O Connor Oct 23 at 7:32
  • You need something to supply 5V. A battery pack is likely to variable and won't be 5V. If the battery pack is 6V or more I would look at a UBEC. They are inexpensive and efficiently produce 5V from a variable voltage. – joan Oct 23 at 8:24
  • Yeah UBEC is a good one. I want to use only one 4x AA battery pack for both the Raspberry Pi and for the motors, which means the battery pack is connected to the Raspberry Pi with UBEC in between and the same battery pack will also be connected to the motors with L293DNE in between. Is it usually? Because sa far I have seen, remote car has only one battery pack. – O Connor Oct 23 at 9:23
  • That sounds okay. Do you realise that 4 AA batteries will only power the Pi and motors for a short time? – joan Oct 23 at 10:30
  • No I do not know how long 4 AA batteries can power both the Pi and the two motors. If that short, I will go for 6 AA batteries or a phone chargeable power bank. That is not the problem. My question is more about using one battery pack to power both the Pi and the motors, because many tutorials, articles and diagram images shows only one battery pack connecting to the motors and shows nothing connecting to the Pi. That raises my question and you said: that sounds okay. So I will do that. Do you think people uses two power suppliers when they build a remote control car with Raspberry Pi? – O Connor Nov 7 at 11:25

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