SM4378 N-Channel Enhancement Mode MOSFET

My apologies if this is posted in the wrong channel. I am looking to replace the aforementioned MOSFET on a customers board but had a little trouble finding this MOSFET on the DigiKey site. Any help is greatly appreciated! Take care…
P.S. I have attached the datasheet AND an image of the part…

sm4378nskp.pdf (295.6 KB)

Hello @TallyTech,

This part appears to be close:

Request another set of eyes to verify the substitution.

Best wishes,


Thank you for checking AND your reply to this request.

I found a few which more closely match the gate charge and input capacitance specs of your part. It may not matter in some applications, but it will affect how quickly they turn on and off, and how much power they consume during the switching periods. Lower gate charge and lower capacitance tend to reduce switching power losses and increase switching transition speeds, while lower Rds-on specs reduce power loss during the time the MOSFET is fully turned on and conducting current. Generally speaking, there is a trade-off between lower gate charge and input capacitance specs vs. lower Rds-on specs.

Your part has a max total gate charge of 21nC with Vgs=10V and max input capacitance of 1100pF with Vds=15V, and its max Rds-on spec is 8.5mΩ with Vgs=10V.

Here’s a link to the parts I found for you comparison:

These all would likely behave quite similarly in your circuit.

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Yeah, I see your point and “Thank YOU” for sending this info. I have this saved and once I get my orders together will be ordering. Take care and thanks again for your assistance and level of detail. Take care!

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