Multiple MOSFETs to share current load?

[Student52]

Background:
Hi!
I'm designing a spot welding apparatus. I won't build it until I have more experience, and under supervision of an engineering student.

Mostly doing it to challenge myself to learn more.
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Question
The spot welder will use 12 V capacitors and output around 1000 ampere for a very short time.
Is it possible to use multiple MOSFETs to share the load?

If so I can design that part of the circuit so that multiple MOSFETs are controlled by a single hi/low logic signal, and together they can handle the high current.
If I want multiple MOSFETs to share the same load, do I just connect the gates from each MOSFET to the control signal lead, drains of all MOSFETs to the earth side of the load and the source of all MOSFETs to the 0 V from the power source?

Of course I'll use pull down resistors and a number of other components, but do I need to isolate each MOSFET's gate or can I just connect all gates together and connect this common lead to the signal output?

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Again, I won't build it until I have more experience, and have the supervision of an experienced engineering student.


Would really appreciate your help, I'm eager to learn.

This paint sketch illustrates what I mean.

[Kleinstein]

For a switching application one can parallel MOSFETs in parallel to share the load. However one should not directly wire the gates in parallel, as there is a chance the circuit could oscillate, due to a combination with parasitic inductance and drain-gate capacitance. The simple and possible way is to use individual gate resistors to isolate the MOSFETs from each other. Another point to watch for is parasitic resistance and also inductance as these can also effect the way the current is shared.

Usuall first start smaller with something like 2 or 3 MOSFETs in parallel. For a lot of large MOSFETs the gate driver power might require to use separate drivers anyway, as the capacitance can get to large to use a single driver.