Technical help reqd! - Transistor selection

Help required from clever people!

I’m currently using this transistor in my DIYBMS project - SI2392ADS-T1-GE3

All working fine, in an effort to reduce board costs, I’m thinking that this replacement device would be similar in operation

PMV65UNEAR - MOSFET Transistor, N Channel, 2.8 A, 20 V, 0.063 ohm, 4.5 V, 700 mV

The basic requirements are for a transistor to work from an ATTINY 3.3v pin and be capable of switching up to 2.5A and up to 4.5V.

Thanks in advance for any help!

The 2nd one actually looks like a much better choice. It has a lower Rds (on resistance) at a lower gate voltage than the first one. You would be running it close to its specified current limit so that is something to consider. The voltage rating seems fine.

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Thanks for the feedback!

Frogmore makes a good point about running a component close to its max rating.

A good engineering design rule of thumb is to - when possible - run a component at ~50% of its max rating.

At 2.5 Amps, the difference in heat dissapation between the two (based on the device Rds) is ~100mW.

One thing I noticed… The PMV65UNEAR part is listed as out of stock on the page at the link above.

Typically it now says “No Longer Manufactured” !!

So much for that idea, eh? :frowning_face:

Luckily I never got around to using that part.

This now looks like a better alternative!

IRLML6244TRPBF - MOSFET Transistor, N Channel, 6.3 A, 20 V, 0.021 ohm, 4.5 V, 900 mV