Hi:
We use LM5050 to control three low-Rdson MOSFET(60V/1.4mohm) as a Oring-Diode for 28V/100A output. A separated 10V auxiliary power to supply this IC, and OFF pin was connected to GND,
The abnormal occurred in the no-load and light load condition, we observe output voltage waveform, the output voltage drops 0.5-1V drop with uncertain time period, the drop lasts 0.5~1ms and the interval is about several ms to teens of ms, it looks like the Oring-MOS gate was disturbed by the noise, however when we measure the waveform of the gate, once the probe of the scope was touch the gate pin, the abnormal was disappeared, so we cannot confirm the output voltage's drop come from the gate driver's abnormal.
We also use the above circuit in two DC/DC converters which was used as parallel output by droop current sharing method, while the DC/DC applied synchronous rectifier. Occasionally, when one DC/DC converter startup as the other DC/DC keeps off, we measure the voltage before the Oring-MOS in the off converter. It looks like the LM5050 gives a wrong signal when the first DC/DC strartup, when we measure the waveform of the output of LM5050, the abnormal was gone. Even one probe(we use differential probe to grasp the waveform) touch on the LM5050 pin-5, LM5050 operate normally. We suspect LM5050 has weak noise immunity.