Hello,
I am looking at designing in 2x DRV8850 into a product to replace an Allegro A3906. I need more current drive and the inbuilt LDO would be good too. The A3906 has 2 inputs (IN1, IN2) to control each full bridge, brake, coast, fwd, rev. A lot of similar drivers use this approach, or a DIR and PWM input. I am driving two DC motors in my product.
One problem I have is the DRV8850 requires 4 lines to control each FET on the bridge, this would be 8 lines from my micro instead of the current 4. This is a problem as space is at a premium on the layout. I wouldn't be able to use external logic to invert control signals.
I guess my question is, is there an elegant way to drive the DRV8850 with only two IO lines (both capable of PWM) to achieve forward, reverse and brake?
Kind regards,
Ian.