Multiphase Operation / External Clock possible?

Hello,

As Tonie mentioned, the LT4295 doesn't have built in support for synchronization or multi-phase operation I recommend you look at either the MAX5974 or the MAX15159. These are standalone DC-DC converters that can be paired with the LT4294 or MAX5995C IEEE 802.3bt PoE PD interface. The MAX5974 has a SYNC pin but would require a separate clock source for the 180 degree phase shift. The MAX15159 is a multi-phase converter and its evaluation kit (MAX15159EVKIT) demonstrates a dual-phase flyback converter design.

It all depends on why you want two LT4295s. If you are trying to combine power to exceed with IEEE 802.3bt limits, then you are better off with two separate LT4295's stages and load balance with the LTC4370 Tonie mentioned. Either that or look into the MAX5996C PD controller (also on the MAX15159EVKIT) which allows multiple inputs to drop share. If you're trying to do something else, please let us know.

Best Regards,

Eric

Especially when galvanic isolation between the inputs must be maintained, a multiphase solution could be more problematic than balancing afterwards; I hadn't really thought this through. Otherwise, the synchronization signals would have to be galvanically isolated. This would require a corresponding clock generator, digital isolator and two extra power supplies. Otherwise I would prefer the solution with the MAX15159.