Locked Anti-Phase on VNH2SP30


I need some clarification regarding the VNH2SP30 motor driver ( pololu.com/catalog/product/537 ), they support braking.

  1. Does this mean that VNH2SP30 motor driver can also be used for locked-antiphase? If so, what is the way to connect them for a locked-antiphase drive.

  2. Do the motors coast or brake between PWM cycles?



There are relatively long switching delays for the two input pins (see the datasheet for more information). Since locked-antiphase drive requires high frequency PWMing of the direction inputs INA and INB, locked-antiphase operation is impractical with this driver.

What do you mean by “between PWM cycles”? Do you mean “during the low phase of the PWM cycle”?
From Table 14 of the datasheet:

Practically speaking, the motor will coast during the low phase of the PWM cycle, but it’s slightly more complicated than that. For example, if you hold the PWM pin low and configure the INA and INB pins for forward drive, the motor will coast in the forward direction but brake in the reverse direction. This is because one of the high-side MOSFETs is turned on (by the high input pin), which allows for current to circulate in the direction dictated by the other high-side MOSFET’s body diode.

- Ben

Thank you for the prompt reply. It was very helpful :smiley: