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LTC4376 for protected load sharing?

Category: Datasheet/Specs
Product Number: LTC4376

Hi - I'm trying to figure out if I can safely use two LTC4376 to load share/protect my power supply. I've got a 28V/250W input (up to ~9.3A, which is higher than the 7A LTC4376 rating) and want to diode or with another supply that will be between 24-32V. Ideally, I'd like to use 2x LTC4376 in parallel between my 28V supply and the system voltage, but the datasheet doesn't mention anything about using LTC4376s for load sharing with a single power supply - only 2 or more. Is there risk of damaging the device by using it like this?

In simulation, the LTC4376s share the load perfectly (~4.5A each with a 9A load) with a single 28V input, keeping both LTC4376s below their 7A limit. Using the eval board, the 2 LTC4376s ended up with slightly different voltages on their input (probably mostly in part due to my terrible cabling) and the current sharing was pretty uneven, which made me worried that I might go over the 7A limit should the devices share as unevenly as I saw in the lab with a minimal voltage difference.  I had 27.86V on the input of one LTC4376, which put out about 1.2A, and then 27.88V on the input of the second LTC4376, which put out about 2.8A for a total load of 4A. Input voltages were measured on the pins of the LTC4376, and output currents with an inline ammeter off board.

If anyone has any thoughts to share I would greatly appreciate some input.

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