I'm using the STM32F103C8 microcontroller to drive a BTS7960 H-Bridge module.
I have already experienced the peculiar characteristics of the module, including the fact that both EN pins must be active in order to run the connected motor in any directions and the directions are only controlled using the separate PWM pins. With this in mind, three pins are in use, including one EN pin (the two EN pins are connected as they must be used together) and two PWM pins. The controller is connected through a TXS0108EPWR logic level shifter.
I tried the motor controller before, but I connected the EN pin manually to the VCC while the PSU and microcontroller was already powered on (the EN pin was not driven by the microcontroller). The motor was running fine in both directions, while driving the PWM pins.
Before connecting the EN pin to the microcontroller, I performed a test measurement using a Saleae logic analyzer and I experienced that there is notable noise at startup and shutdown of the microcontroller (power on and cut-off) at all of the pins, including the ones that are connected to the motor controller. If I will connect the EN pin, that means there will be a time period, when all of the pins are active, even if it happens for a short time.
The following measurement was performed at the microcontroller pins (I left the EN pin unconnected from the motor controller, the PWM pins were connected).
I also tried push-pull configuration, using the TXB0108PWR level shifter, but the result was the same. When using direct connection with the microcontroller (without level shifting), the result was also the same.
I tried to use capacitors with various values at the power rail but it did not change the situation.
My main question: Will this condition cause any issues for the motor controller? I’ve read several comments before about people burning this controller for unknown reasons and I'm afraid that this might be one of them. I haven’t tried connecting all three pins at power on and power off period due to this reason (I try to avoid connecting the EN pin until it is clear whether this could be a potential issue).
Thank you in advance!
