PsoC4 Halted unexpectedly due to EMI? | Cypress Semiconductor
PsoC4 Halted unexpectedly due to EMI?
I am using the CY8CKIT kit to control a 12V sensored brushless motor.
I use 6 output pins to drive the 6mosfets through appropriate gate drivers.
I use 3 input pins for rotor position feedback (3 hall sensors).
The problem is:
When I increase PWM duty cycle to progressively accelerate the motor I reach a point around 50-60% duty cycle in which the microprocessor HALTS.
The motor continues running at that constant speed because the hardware blocks (PWM and LUTs) continue working perfectly, but I know the software is halted because I have a blinking led that stops blinking.
Some more data to understand the problem:
The psoc4 is powered from kit on-board 3.3V regulator. I provide 5V to the kit board with a linear 7805 regulator from motor battery.
When I use 7.4V battery the problem doesn’t happen.
When I use 12V battery the problem happens. But:
If I connect theusb cable to the PC AND enter the debug mode to try to understand the problem then the processor doesn’t halt.
If I add 100 ohm series resistances in all mosfet gates to slow down turn on and turn off then the processor doesn’t halt, but the mosfets overheat due to cross-conduction even with 4% deadband implemented in the PWM. This makes me think the problem is somehow related to EMI.
To summarize, I would like to understand:
-What is the mechanism than makes the microprocessor HALT?. The 5V and 3.3V power lines are very stable and the reset is pulled up to 3.3v. Moreover If a low voltage condition is detected in the power lines shouldn’t the psoc4 RESET instead of HALTING?
- Is there anything I can do apart from increasing Rgate? Why is the problem apparently solved while in debugging mode?