Hi Sam
That 50mA will be the total. That regulator does nothing else but provide a 5V output. It should handle 50mA without any problems at all.
Cheers bob
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Hi Bob,
Good catch, I agree with your assessment of that circuit, the 5V output will only operate whilst VM is 6.5V or higher. This is likely to be the case in 99% of applications but it’s worth clarifying for those that use this driver with a low input voltage. I’ll make a note to have that product page updated shortly.
Hello!
I am looking to control a 12V DC linear actuator with a no-load current of 0.8A and a max-load current of 3A. It will run for approximately 10 seconds at a time. It will not be working very hard, so I don’t think it will ever need to get above 1.6A.
I would like to know if 1. the Makerverse Motor Driver 2-Channel is the best thing to achieve this? And 2. Am I able to power a Raspberry Pi Pico from the driver?
Probably also worth mentioning I would use a 12v 2A power supply.
Thanks so much! 
Hi @James114553, welcome to the forums
It sounds like our little motor driver could work out quite well assuming your guess about the current requirements are correct.
The 5Vo pin can power the pico if you connect it to the Pico’s VSYS pin via a diode
you can even tune the current limit if you decide you want to leave some safety in there.
in short, sounds super viable, but your mileage may vary. Best of luck with the project!
ps. we haven’t tried bridging this driver before, where you combine the channels together to double the output current. I’m not sure if it’s possible since there’s no mention in the datasheet. proceed with caution and if you decide to try let us know your results! (letting out the smoke, or success 
)
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Hi James
I don’t intend to be destructively critical here BUT,
It had better not as you also state
Not much room for error here is there.
It never stops amazing me why quite a few hobbyists/makers insist on using a power supply that is barely up to the task. Then run in ever decreasing circles trying to figure out why the project does not quite live up to expectations.
Quite often the problem lies because a few mA gets added here and there as small add on requirements. Not much when you say it quick but when added up the power supply has been stretched to the limits.
In this case why not go for a 4 or 5A supply. The stall current is apparently 3A so even that is not considered with your 2A supply.
Have a think about it.
Cheers Bob
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Thanks for the feedback Bob! I am new to fiddling with electronics in any meaningful way, so can do with all the help I can get. In this case I was more worried about having to much current, but I hear what you’re saying.
Hi James
Can never have too much available.
Cheers Bob
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Hey Bob,
Stellar response, defiantly a great motto to work by. Just be careful not to overload anything
Cheers,
Sophia
What diode would you suggest ?
I’m looking at running a Raspberry Pi Pico (Power fed to pin 39 (VSYS) from the motor driver)
2x of the DC motors, a button/switch so can program two speeds that the button will switch between, and an LED or two.
I was planning on running 4x AA batteries (6V) as thats what the motors are rated at.
That would however drop the voltage being supplied to the raspberry pi VSYS pin (pin 39) to 4.5V right ? (Since this has a 1.5V voltage drop)
A diode would likely drop this even more and that takes it below the 5v +/-10% that VSYS is rated for.
I’m seeing a voltage drop of 0.7V across these for example which would drop it back to 3.8V or well below spec (4.5-5.5V) for that pin on the raspberry pi.
That would mean needing to use a 5/6x AA battery pack right ? However this would now provide 7.5/9V for the motors which is too much for them.
Hi Nicholas
A bit confused here.
What exactly has the 1.5V voltage drop.
Where is this diode going to be in the circuit.
That is normal for these diodes. Again where do these fit in the scheme of things
If they are flywheel diodes across the motor they will play no part in things until the motor is switched off with PWM or other means.
The stall current in the text description will be the same as the start up current (inrush) and has to be considered when working out power supply capacity. I don’t think AA cells will last too long if this motors are stopped and restarted too often at 1.5A per go per motor.
Cheers Bob
A circuit of what you intend would be helpful.
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This is essentially what aiming to make but using a Pico rather than a Pi 3 and not the ultra sonic / linefollowing
So the plan is
From what the listing for the motor driver shows it has a 5Vo now (However requires 6.5V to do that - e.g. a 1.5V drop from the source) The thought was to use that to power the pico rather than neerding a second power source to keep the price down as planning on doing this with a class. Preference is not to use Lipo’s for safety reasons with students.
Michael up higher here (Dec 2023 post) mentions that the 5Vo pin can power the pico if you connect it to the Pico’s VSYS pin via a diode. my concern with taking that route and including a diode is it drops the voltage below what the pico expects from pin 39 (VSYS)
The first push button would be used for setting state of the motors to high / low, and the other for setting the LED’s on / off as headlights (With the option of swapping out the 2x single colour LEDs with 2x WS2812B ones cut from a strip (This would obviously require some different wiring with the power for them coming from the vbus pin))
This would be the diagram when using 2x of the WS2812B LED’s
Powering the MCU and the motor from the same battery pack has to be done very carefully so that load fluctuations on the battery pack as the motor starts and stop don’t cause fluctuations in the battery voltage and unexpected restarts for the MCU. This would be very difficult to accomplish with AA cells, which have a high internal resistance and a significant voltage drop under load.
One option is to use a battery pack that has the ability to cope with these fluctuations, such as LiOn, with separate regulators for each supply (which would also minimize interference from the motors). Or use two separate AA battery packs, one 4 cell for the motor and one 2 or 3 cell for the MCU. If you use separate packs then be sure to provide a good common earth connection between them in order to ensure that logic levels are correctly maintained.
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Hi Nicholas.
Firstly heed what Jeff says.
That makes a bit more sense. I see now where that 1.5V drop is coming from. The motor driver has an on board linear regulator. These have a “drop out voltage” which I think for that one is 1.5V. This does not mean that the output will always be 1.5V below the input. It means the input has to be 1.5V ABOVE whatever the regulator output is, in this case 5V. This means that for 5V output the input will have to be 6.5V or more. I am not sure what happens should the input fall below this (I have never actually tried it), it could mean the regulator shuts down and you get nothing out.
You can power the Pico via Vsys with between 1.8V and 5.5V as it has an on board buck/boost converter to 3.3V.
If you go to this web site
And scroll down to section 4.4 and 4.5 you will find a detailed schematic and description for powering the Pico. The Pico has its own on board schottky diode to isolate a USB or Vbus supply but an external diode to Vsys would be desirable. Especially if your supply to Vsys is batteries to prevent USB or Vbus from back feeding into batteries in an uncontrolled manner.
So you could power the Pico from a 6V battery source via a diode with a 0.7V drop and be just under the 5.5V Pico maximum. BUT remember the nominal 6V will be a bit more with fresh cells. Normal Zinc/Carbon types are actually 1.55V when fresh.
You might be better off with 4 NIMH or NiCad rechargeable batteries which might have a bit more grunt than Zinc/Carbon. This will give you a nominal 4.8V for the motor (disregard and do not use Vo) and a nominal 4.1V for the Pico which is well within the Pico Vsys input range.
Jeff’s idea of 2 separate battery packs has a lot of merit and for motor use would be a good idea for the reasons outlined in his post. That is what I would do anyway, always use a separate supply for motors.
Cheers Bob
Just had a look at your lower diagram. without a USB connection you will not get any output from Vbus. Refer to schematic in Sect 4.4 in above link. There is a diode in the way.
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Thanks for your help Jeff and Bob
and for the datasheet
I’ve done an updated diagram based on what you’ve both said.
So it now has a second battery pack (one with a Micro-USB end) to power the Pico separately as Jeff suggested.
Since the Pico is getting its power via the 2nd battery pack which is plugged into the USB that should solve the VBUS not having the power for the 2x WS2812b LED’s.
When programming the Pico it would simply be the USB is changed from the 3x AA battery pack to the USB plugged into the computer so not being fed from two different sources.
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Hi Nicholas
That should do it. The only remaining problem is if the AA batteries have enough grunt for the job.
Cheers Bob
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Thanks Bob,
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Thanks @Jeff105671 and @Robert93820 for helping out on this one.
Very throughout explanations and assistance as always
