Hi all,
I am using an LM5106 gate driver to switch a synchronous boost converter, the MOSFETs I am using are IPP075N15N3G.
I have experienced quite a few times the failure of the LM5106 driver now: permanent short circuit between VDD and GROUND.
I believe this might be caused by voltage transients due to high leakage inductance in my PCB, it is my first experimental PCB design ever, so I am not surprised (if you have any good suggestion/reference for layouts it would help). The boost converter switches at 200kHz, Vin = 10-20V, Vout=20-40V, load up to 50W.
I noticed in the LM5106 datasheet, how HS (pin) transients below ground can permanently damage the driver, I assume this type of transient might have permanently damaged the gate driver (although I am not 100% sure). I would like to include a protection against these transients in my next prototype.I read in the datasheet, pag. 15-16, that Schottky diodes can be placed externally between HO and HS or LO and VSS (ground). I would like to include these Schottky diodes in the future design.
So, should I connect the Schottky diode between HO and HS (Schottky #1) and also between LO and VSS (Schottky #2) in order to avoid this transient? where:
Schottky #1 Anode -->HS
Schottky #1 Cathode -->HO
Schottky #2 Anode --> VSS
Schottky#2 Cathode --> LO
Also can you suggest the specs of these Schottky diodes? or any diode part number that could be used?
Thank you very much,
Leonardo