L298 vs. TB6612

Hi gents,
I saw a few projects using the ancient L298 H-bridge. I had good results with the TB6612 (sparkfun or Adafruit) in a DC-motor with step/dir interface project.
The efficiency of the 6612 is much higher IMHO

Just my 2 cents of wisdom

Hey, @o_lampe ,

I think it has been mentioned before on this forum, and you’re right, this driver is much newer than the L298N, and will support higher PWM frequencies than the L298N.

However, due to the fact the channels have logic for brake mode, eg they combine the inputs to decide the two channels output, I think you’ll only be able to use one of the half bridges per module when driving a BLDC. So you’d need one module per phase.

Compared to the L298N that’s a little less convenient, as on that module you can use the channels independently. Also it will handle quite a bit more current…

Nonetheless, given the price of these TB6612 modules it might be interesting for some people to try them :slight_smile:

I think, the brake mode doesn’t connect two outputs directly to shortcut the motor coil, but they are both switched to GND.
Also it felt like the L298 use PWM not in switch mode but for linear DC control, which produces a lot of wasted energy and heat.

The L298N is based on Darlington transistors, rather than MOSFETs. For this reason is has slow switching times and wastes a lot of energy during the switching. Compared to a modern MOSFET it’s very slow and wasteful.
But on the other hand the part is a winner… it is inexpensive, robust, versatile and simple to use, so even 30 years after its introduction people are still buying it :slight_smile: