12V "dumb" motor driver IC?

@smithdrewsmith

It is unclear to me what you are alluding to?

What is a "dumb" motor driver circuit?

Does your project involve a simple DC 12 volt motor such as in a battery powered hand drill?

Is the button press a simple selection of direction while being pressed?

Do you want speed control?

There is no reason for a motor control circuit to draw power when not in use.

Hi @smithdrewsmith,

Whilst @robotbuilder was typing his answer above, which encapsulates most of my puzzlement with your question, I did a quick search of articles by Bill @dronebot-workshop discussing "h-bridge", knowing that dc motors are often controlled h-bridges.

You may find an answer, or perhaps or more specific question or two that you can pose. The following link should show a summary page of a few relevant articles, each of which will have a video and blog.

https://dronebotworkshop.com/?s=h-bridge

Good luck, and please feel free to post a follow up question, Dave

@robotbuilder 

Thanks for asking for clarity.

By "dumb" I mean not controlled by a microcontroller.

Every motor driver I have found has a maximum voltage for the controller inputs (clockwise, counter clockwise) of 7 volts or less. Running any of these in a car at 12V would require a regulator, which as I understand it will be drawing power as long as it is connected to 12V, regardless of whether the motor is being operated.

Yes, I need to drive a simple motor at 12VDC.

Yes, a button press would supply 12V to the driver as a signal to turn the motor one of two directions.

No, I don't need speed control.

I'm hoping to find a motor driver that I can drive from 12v switched signals while having the driver continuously connected to 12v but not drawing power unless it's actively driving motors. I would rather not build discrete mosfet h-bridges because there are 8 motors involved in my project.

Thanks!

@davee Thanks for the link, I missed the generic H-bridge video.

I'm looking for a driver that accepts a logic voltage of 12V. I haven't finished the video, so it may be coming.

@smithdrewsmith 

Yes, I need to drive a simple motor at 12VDC.

Yes, a button press would supply 12V to the driver as a signal to turn the motor one of two directions.

No, I don't need speed control.

Then maybe a simple self centering toggle switch for each motor as I show here?

https://forum.dronebotworkshop.com/motors/how-can-i-use-a-36v-dc-motor-encoder-with-an-arduino/

" Just turning them left or right without any speed control can be done with simple self centering toggle switches, much like driving a tank with two levers ... "

Hi @smithdrewsmith 

I haven't checked, but suspect all of the videos will use a microcontroller, because the forum is about computer controlled machines, etc. Hopefully the videos will give some general guidance and information.

If there are logic inputs that need to be driven by pushbuttons, or even continuously held high, that are only rated for say 0V to 5V, then there are numerous options, starting with a simple potential divider consisting of two resistors, such that the push button applies 12V power to the 'top' resistor when the switch is closed, and the junction of the resistors outputs 5V, to the logic input

When choosing resistor values, check to see if the input will draw a substantial current, compared to that flowing through the resistor chain, because this could reduce the effective voltage applied to the input.

As always, the chip data sheets are your friend, and the Internet means they are usually only a few mouse clicks away. Forum members of a certain age will recall persuading sales reps to part with paper copies .... 😊 

Best wishes, Dave 

My project is a little more complicated than that and requires tactile switch inputs due to size restrictions and method of actuation. Thanks for the help though!

@davee thanks for the additional feedback. I've looked at a bunch of drivers and no joy, but I'll keep looking. There is one listed in the DBW video capable of 12V logic, but it's significantly overkill.

The voltage divider option had occurred to me, as well as using optoisolation, but I was hoping to avoid that.

Hi @smithdrewsmith,

 I am not sure if your reply immediately above refers to my or @robotbuilder's suggestion. If you use the "Reply" button at the bottom of the message you are replying to, it will add  the name of the recipient into your reply, so they know who it is addressing, and also get a warning that they have been mentioned in a new message.

I obviously don't know about your project, but I would have thought, simple 'tactile' switches could handle 12V, at a small current of say 1mA when pressed, for my resistor potential divider suggestion.

Driving motors directly is clearly a different matter.

Best wishes, Dave

Hi @smithdrewsmith,

   Our last replies have crossed in the ether.

   Alternately, there are some low quiescent current regulators around, but you may need to do a bit of searching.

e.g. https://www.st.com/content/st_com/en/products/power-management/linear-voltage-regulators/low-dropout-ldo-linear-regulators/high-psrr-ldo-regulators/ldln025.html

claims 12 microAmp no load current, which will be tiny for any batteries capable of driving motors.

No doubt there are other competitive solutions as well - I haven't looked.

Just another wacky thought.

Best wishes, Dave

@davee you're correct, my non-reply comment was to @robotbuilder. I thought I used the reply button.

Thanks for the idea of low power non-loaded regulators, that should do it. This project has the potential to set connected to battery for months without use, but I think I can live with 12microamps.

@smithdrewsmith 

Ok. Hard to give suggestions without fully understanding the setup.

I assume by tactile switches you meant capacitive touch switches or touch screen.

https://randomnerdtutorials.com/esp32-touch-pins-arduino-ide/

@robotbuilder I truly appreciate your help. I dont want to get into details of my project because I'm constrained by quite a few things that are difficult to describe.

By tactile switches, I meant these: