I am trying to use the High-Power Motor Driver 18v15 (P/N 755) for a project, and I am seeing some strange results when DIR is set Low. The ugly block of PWM-like switching is the result of constant signals on the PWMH and DIR pins highlighted in red.
The driver is being controlled by an Arduino. We have a 10 V power supply providing power and a 10 Ω dummy load on the output. The Reset pin is held high to V+ through a 20 kΩ resistor. We tried giving PWMH a 50% duty cycle PWM signal and observed similar bizarre results whenever DIR was set low. We felt this screenshot was most illustrative of our dilemma. The scope should be reading 5.0V/division, but we do not have the 10x attenuating probe hooked up to it right now.
Our loop runs 1 second each of the following constant states:
PWMH = Low / DIR = Low
PWMH = Low / DIR = High
PWMH = High / DIR = Low
PWMH = High / DIR = High
Please let us know if we are missing something! Thanks for your help.