DRV8873-Q1: Using Internal Current Sensor for bidirecitonal measurment

What if I measured IPropi1-IPropi2 with true differential ADC?

I taught when the motor turns one direction IPropi1 has some value and Ipropi2 equals zero and this particular equation gives to me one direction's current value.

And when the motor turns other direction IPropi1 equals 0 and IPropi2 has some value, this equation gives me a minus value which indicates the direction.

What do you think about this approach?

Hi Erdem,

If you are trying to measure the current from the power supply through the motor, you can measure IPROPI1 voltage when the current is flowing from OUT1 to OUT2 and IPROPI2 voltage when the current is flowing from OUT2 to OUT1.

As an alternative, you can connect both IPROPI1 and IPROPI2 together as shown in Figure 14 of the datasheet.

When the current is flowing from drain to source of HS1, IPROPI1 will create a voltage on the IPROPIx resistor. IPROPI2 provides no assistance and is effectively HiZ because the HS2 current is either no flowing or flowing from source to drain.

When the current is flowing from drain to source of HS2, IPROPI2 will create a voltage on the IPROPIx resistor. IPROPI1 provides no assistance and is effectively HiZ because the HS1 current is either no flowing or flowing from source to drain.