PaulS:
We'll need to see a full schematic showing how you have connect the chip to the Arduino and to the motor and power supply.We'll also need a link to the data sheet for the chip.
data sheet for the chip http://ww1.microchip.com/downloads/en/DeviceDoc/11195c.pdf
Chip connected to the Arduino as on my pic in the first post. It doesn't connected to motor. I try to control a remote of the skateboard. The power supply of the remote is 3.7V, on Pot wires goes 3V, on wiper in the midle position 1.5V