Other Parts Discussed in Thread: LM5109, LMG5200
Hello,
I'm using 3 LM5109A to drive 3 phase 200W BLDC motor. I've included schematic with component details.
VIN to the power MOSFET half bridge stage: 20V-33.6V (Battery power)
MOSFET: BSC057N08NS3 G from Infineon Technologies
Resistor value of driver output to FET gate: 4.87 Ohm
Bootstrap diode part number: MMBD4448HT-7-F
Resistor value in series with boot diode: 100 Ohm
I'm facing similar failure as posted with title 'BLDC motor controller problem'. Few boards work for half an hour and few boards run few minutes and then LM5109A and MOSFETs die randomly. When the driver fail you can hear a "hiccups" in the commutation.
I would like to mention the board is based of older version that runs for more than a year and drives 70W motor without any known issue.
I also provide waveform of HB,HS,LO to GND.
After reading carefully the datasheet and two relevant posts here, I've replaced resistors in series with boot diode to 10 Ohm and add two schottky diodes on HO-HS and LO-GND, and the driver and MOSFET still failed with the same phenomena.
What could be the possible diagnosis of this issue?
Appreciate your help.