First, here is a quick refresher on the real 4110 mosfets
Manufactuer Name: IRFB4110PBF
Datasheet: IRFB4110 Datasheet
VDSS = 100V
RDS(ON) = 3.7mOhms (typ) 4.5mOhms (max)
ID = 180A (silicon) 120A (package)
So what does all that mean?
Above are the three most important terms.
Translated to shop talk they are:
Max Voltage = 100V
Inline resistance = 3.7mOhms
Max Current = 120A
The RDS(ON) is perhaps the most critical factor.
Heat is the limiting factor in our application and the heat can be calculated in terms of I and R
I^2 * R
I is the current that you are driving through the mosfet
R is the internal resistance.
This shows you that if the internal resistance doubles the heat doubles
Example: I = 100A R=3mOhms
100 * 100 * 0.003 = 30W
This brings me to my point: Counterfeit 4110's
There are 2 parts to a counterfeit
- Appearance and PerformanceAppearance:
I wont get into a big compare and contrast but you can tell right away that the stamp is different above.
These are labeled FB4110 and the date code and logo are in the wrong spot.
This has been discussed: Bobmcree on fake 4110'sPerformance:
The way they fool us is by meeting some of the electrical requirements but not all.
In this case, I bet they meet the max voltage requirement.
Max Voltage = 100V
Inline Resistance = 7.4mOhms (Only for example - not actual value)
If you plug the counterfit in and apply 100V everything is fine
If you run it with 20A or 30A they are still nearly undetectable
Trouble is when you try to crank the current up to 100A
The mosfet will still work, but it will create double the amount of heat.
100 * 100 * 0.0074 = 74W
This is a killer.
A true IRFB 4110 mosfet is a very powerful device.
I personally run a 6 fet controller that does not even get hot at 60V 60A
Inferior mosfets require 12 or even 18 mosfets just to reach 60V 50ASo the point of writing this up is to make sure that the good name and benchmark we have established with the term "4110" is not misused, abused, or confused.
There are a rash of new controllers coming out with (what look like) these counterfeit 4110's.
I would like to remain unbiased so I am not going to name any names.
Please, if you have the time and resources could you add to this posting by sharing any test results, experiences, or knowledge you have on the subject?
EDIT_1 - Added note that 7.4mOhms was a made up number for example purposes. Will correct with real number once measured.