L6472 overcurrent error due to ESD pulse during EMC test
We use this part L6472 more than 10 years, and in the latest design we have serious troubles with ESD. The device current limit is set to highest level of 6A, but during an ESD pulse, it throws the message "over-current error", even if the motor wires are disconnected. One single short pulse leads to a permanent error, as the BUSY signal is never reset by itself, steps might be lost and there seems no way/method for auto-recovering.
Interestingly, the package HTSSOP28 seems much more sensitive than the POWERSO36. We use both packages in 2 Boards with very similar layout, only the package of L6472 had been changed.
Is there any experience or explanation of the manufacturer, that the POWERSO36 is less sensitive to ESD?
Obviously there might be some internal coupling into the current measurement/internal ADC, how to overcome this problem with external components? Our design is very similar to the documentation of eval Board eval6472h.pdf.
Additional 100nF at VREG, VDD or VBOOST to GND do not help also.