[TasosVL]

Hello all, my first post on this forum.

I am building some v0.4.3d THT boards and i am struggling with finding the STP62NS04Z mosfet. Seems its production has stopped. What are some alternative mosfets with internal clamping? I am thinking about using another mosfet with similar characteristics and add external clamping with zeners.
Anyone have figured out another solution?

[Walterronny]

ive been trying to find any good replacement , found this one but too obsolete: STP70NS04ZC . I decided to go with 0.4.4d.

[PSIG]

Your choice, depending on the electrical environment, but popular replacements are common N-MOSFETS with logic-level gates, such as the IRLZ44 and many others. Adding gate protection is again your judgment. I would suggest using a MOSFET worksheet, such as this.

[JHolland]

I am building some v0.4.3d THT boards and i am struggling with finding the STP62NS04Z mosfet. Seems its production has stopped. What are some alternative mosfets with internal clamping? I am thinking about using another mosfet with similar characteristics and add external clamping with zeners.

Why do you want a MOSFET with a gate clamp? just use a conventional MOSFET with a decent avalanche rating.

[TasosVL]

ive been trying to find any good replacement , found this one but too obsolete: STP70NS04ZC . I decided to go with 0.4.4d.

The 0.4.4d uses the vnld5090 for injector drivers. It is a good solution to use this in the THT board just need some extra work on soldering.

[TasosVL]

I am building some v0.4.3d THT boards and i am struggling with finding the STP62NS04Z mosfet. Seems its production has stopped. What are some alternative mosfets with internal clamping? I am thinking about using another mosfet with similar characteristics and add external clamping with zeners.

Why do you want a MOSFET with a gate clamp? just use a conventional MOSFET with a decent avalanche rating.

The STP62NS04Z mosfet has an internal zenner across drain and source. That eliminates some external components. When the injector closes, the reverse (negative) voltage that appears to the mosfet due to inductive load doesnt exceed the internal zener's voltage. That inductive reverse voltage kick helps the injector to close faster.

[TasosVL]

Your choice, depending on the electrical environment, but popular replacements are common N-MOSFETS with logic-level gates, such as the IRLZ44 and many others. Adding gate protection is again your judgment. I would suggest using a MOSFET worksheet, such as this.

Yes mosfets such IRLZ44 will work but how do you manage the inductive voltage kick from the injector? Wont you need some fast diodes for that?

[JHolland]

Yes mosfets such IRLZ44 will work but how do you manage the inductive voltage kick from the injector? Wont you need some fast diodes for that?

The FET clamps the inductive kick, that is why you need a FET with an adequate avalanche rating.

[EdMcGuirk]

I guess the question in my mind is whether there is a significant difference if the voltage spike is bled off through an avalanche or a clamp. Either way the heat gets dissipated in the mosfet. Choose a voltage just high enough to make the injector close quickly and a mosfet that can handle the resulting heat.

I didn't get a clear answer when I searched clamp vs avalanche.

[JHolland]

Its often better to let it avalanche because you don't get the problem with the high gate voltage during clamping. Amateurs often chose the ST gate clamped FETs because ST claimed them to be 'fully protected', the reality is they have no real protection and ST were widely ridiculed for it.