LMG5200: parallel usage in half bridge

Hi Nubuo,

paralleling multiple LMG5200 is not advised.

The main reasons for this are:

1. If the dead-time(DT) is not set to account for worst case propagation delay mismatch from part to part, you run the risk of cross conduction between High side FET of one LMG5200 and the Low-side FET of another LMG5200.

2.Even if the DT is large enough, the variation between parts will cause one of the LMG5200 to switch first. This device will dissipate all the cumulative Coss losses of all the other FETs that are connected to this node.

One possible way to mitigate this is to split the inductor between the LMG5200s, effectively making this a multi-phase converter. Smaller inductors can be used to split the phases,and a single larger one to provide the DC filtering.

Best regards,

Alberto