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Brushed DC motor driver @3A range, 100kHz+

I would like to suggest DC motor driver at medium power (24V, below 3A) at lower price than high power.
Currently, only High power (12A+) and LOW power(less than 2A) are available, High power driver is too overkill. Usually, 20-50 diameter DC motor need current less than 3A.
Suggested specification are

  1. capable of locked anti-phase with PWM frequency at 100kHz or higher.(if locked anti-phase at 100kHz is not possible, at least make it change direction fastest as possible)
  2. current locking (same as G2 Driver).
  3. an optional version which has no inverse voltage input protection (Because of voltage drop, and I would like to try charging current back to source).

BTW, pin and dimension like G2 driver is preferred.


Thank you for the suggestion. What kind of price are you looking for? Our existing #2992 G2 High-Power Motor Driver 24v13 already does everything you want (the reverse-voltage protection allows current flow back into the source, and the losses in it are minimal), and it is probably not worthwhile for us to make a slightly cheaper version with worse MOSFETs. That said, if you have a high-volume application, we can definitely make some customized units for you with lower-performance MOSFETs to trim the cost a bit.

- Ben

I have tried to measure current between VM and ground, (with VIN = 24V) the result is 23.3-23.5V, So I think that when current flow back to source, some of power will loss due to this voltage different.

Also, G2 driver current limiting is not accurate at low current. It means that G2 is designed to drive high current motor.
For some reason, I happen to find high voltage motor(36V+ with approx 3A current) easier than 24V, 5A.
So I think I need a driver that can set limit to 3A and drive with more voltage.

Also, about PWM frequency, I use a high-spec microcontroller that can output very high frequency so I would like to run at highest frequency available.

I am not sure about this, but I think PWM frequency and current is a trade-off.

I am not sure what you are saying about your measurements, but of course there will be some losses. The point is that the reverse protection MOSFET only adds about 4 milliohms, so the losses from that will be minimal and lower than if you had a lower-performance H-bridge, which it seems like you are asking for.

As for the rest of your feedback, we will keep it in mind as we develop future drivers. You did not address my price or volume questions, so again, if you do have substantial volume requirements, we should be able to swap some components to better match your application. Please contact us directly with your volumes and target prices if that is something you would like to pursue.

- Ben