MP5016(H) in Parallel

DC-DC Power Converters
#1

I am wondering if it is possible to use two MP5016 e-fuses in parallel to lower the power dissipation.
We need them in an application that can have relative high ambient temperatures (85C) and with a continuous load of 4A the junction will be just on the edge of the thermal limit, so I’m not comfortable with that.

But adding a second in parallel (both set to one half of the allowed current) would lower the total power dissipated in the internal mosfet. Is this possible? I can imagine that the slew rate control could mess up normal operation.

#2

Hi Daan, welcome to the forum!

It depends on the overall current rating you expect to have. If the current is much higher than 5A, there will be an imbalance between the 2-channels of MP5016H devices. The exact imbalance will depend on the Rds_on difference of the 2 channels.

It is possible that one channel might trigger OCP before the other. If that happens, all the current will follow through the remaining channel and cause it to OCP as well.

I would suggest with this device to keep the overall system current rating <= 5A for a 2-channel parallel application.

1 Like
#3

Hi Kareem,
I’ve just tested this on 2 evaluation boards and unfortunately this does not work in the configuration I need it.
I hadn’t read the datasheet properly but if the e-fuses current limiter is triggered for longer than 2ms it shuts of.
If I increase the total load current to ~3A (coming from to e-fuses in parallel, both set to 2A each) the current imbalance pushes on e-fuse into current limiting for longer than 2ms and thus also tripping the 2nd e-fuse.

#4

Hi, One more question regarding the current balance between the 2 e-fuses in parallel. The datasheet does not specify more than the typical on resistance of the mosfet at 1A. Is there some more information regarding the on resistance over temperature, load current, and component to component variance?

#5

Hi daan, depending on the high side of your current limit, you can also opt for a high performance eFuse like the MP5921, which will give you plenty of margin thermally.