0
\$\begingroup\$

Is there any difference between 2N7000 and 2N7002? Can I replace them without changing pre-existing circuits, beside physical/package sizes? Normally for a 2N7000 I use a 100Ohm gate resistor and 1.2MOhm gate to drain resistor. Is it the same for a 2N7002?

enter image description here

edit - here is a electrical characteristic comparison between 2N7000 vs 2N7002

\$\endgroup\$
9
  • 4
    \$\begingroup\$ They are very very similar. Not the same, but nonetheless very very very similar. Did you look at the datasheet? \$\endgroup\$
    – DKNguyen
    Mar 28, 2021 at 5:47
  • 1
    \$\begingroup\$ @DKNguyen yes, But I can't seem to find any useful information. they looks pretty much the same \$\endgroup\$ Mar 28, 2021 at 6:11
  • 1
    \$\begingroup\$ Even in datasheets that directly compare them it is difficult to find the difference. \$\endgroup\$
    – DKNguyen
    Mar 28, 2021 at 6:23
  • 2
    \$\begingroup\$ It seems that 2N7002 is an SMD version of a 2N7000 (TO-92 package). \$\endgroup\$
    – G36
    Mar 28, 2021 at 6:23
  • 4
    \$\begingroup\$ The 2N7002 is in a different package and offers different resistance and current rating. Otherwise similar. \$\endgroup\$
    – jonk
    Mar 28, 2021 at 6:24

1 Answer 1

6
\$\begingroup\$

Question

What is the difference between 2N7000 and 2N7002?


Answer

One critical difference for me is that 2N7002 is definitely logic level trigger, 2N7000 is not so sure.

2n7002


References

(1) 2N7000 / 2N7002 / NDS7002A N-Channel Enhancement Mode Field Effect Transistor - FairChild/On

(2) 2N7002 N-channel Logic Level MOSFET - Components 101 2019jan07

(3) 2N7002 (Vgs(th) min 1V, typ 2V, max 2.5V) Datasheet - NXP 2011sep08

(4) 2N7000/2N7002, VQ1000J/P, BS170 N-Channel 60-V (D-S) MOSFET - Vishay

(5) What is the meaning of “Logic-Level Gate Drive” for the MOSFET? - Toshiba

(6) Logic Level MOS Field Effect Transistor - NTE

(7) OptiMOS 5 and IR MOSFET 60V/80V/100V Logic Level - Infinion

(8) Power MOSFET Driving Big Motor Problem - tlfong01 RpiSE 2019feb09


Appendices

Appendix A - Why Logical Level Vgs(th) is critical to me hobbyist?

  1. In my old 5V Arduino days playing with N-Channel power MOSFET such as IRF540N, I found that its Vgs(th) is well above my 5V Vcc, of the order of 7V. The EE guys then invented clever things called "charge pump" to pump up a cap to 7V to trigger the power MOSFET switch.

  2. I was too lazy to DIY any charge pump and so I gave up, leaving my batch of IRF540N lying in the junk bin to collect dust. My IRF540Ns did stay in the junk bin for 10 years or so, then I heard the good news that new generation power MOSFET's are "logical level" which means Vgs(th) is approx 3V or lower.

  3. And so I threw away my IRF540Ns and got IRL540Ns. I found my Rpi 3V3 logical level GPIO pins can now directly switch them, at least for 500mA of the max rating of some 50+A, with very low Rds(on).


Appendix B - Logical Level Power MOSFET Characteristics

I mainly use N-Channel Power MOSFER such as IRL540N for low current swtiching. For Rpi 3V3 logical GPIO pins, I can already switch up to 6A, so I am happy to use it. I know other users hope to use 1V8 logical level trigger, and there are more and more such MOSFETs coming out. I am showing two cases below.


irl540n


1v8 mosfet 1


\$\endgroup\$
3
  • 1
    \$\begingroup\$ how did I missed that. VGSth voltage is pretty important to me too. I was going to use this in combination with Arduino \$\endgroup\$ Mar 30, 2021 at 5:00
  • 1
    \$\begingroup\$ @JohnCortex the 2N7002 will work OK with 5V CMOS. When you go to 3.3V CMOS then I would recommend the BSS138 instead. To be honest, I would probably recommend the BSS138 over the 2N7002 in just about all cases. The 2N7002 is very old. One day they will stop making it. \$\endgroup\$
    – user57037
    Mar 30, 2021 at 5:46
  • 1
    \$\begingroup\$ BS170, 2N7000, BSS138... not much difference between them, IMO. I've found out that just the Vgsth as a single figure doesn't say much. A chart of Ids vs. Vgs is much better - and that chart tends to be surprisingly similar between many modern-day "logic-level driven" small MOSFETs of this category. They behave very similar. The BSS138 actually seems slower (20 ns) than the 2N7000 or BS170 (10 ns, even down to 4 ns) but again those are paper figures. My favourite would be the old BS170, owing to its 500 mA of nominal current. The Rdson is nothing special in either of them. Pinouts do differ. \$\endgroup\$
    – frr
    Mar 30, 2021 at 7:25

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.