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MOSFET which can on fully at 5V

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kushal nandanwar

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I am looking for logic level MOSFET which can on fully at 5V. With continues current of 3 to 5A
 

SunnySkyguy said:
Search Logic Level MOSFET

Vgs has many options with thresholds that have reduced from 4V to 2.5 to <1 V

Specify RdsON Vds and logic level.
Click to expand...

thresholds 1.5V , can handle 3 to 5A continuously

RdsON < 1mohm
Vds = 50V
logic level 0 to 5V
 

The parameter combination makes no sense. 1 mohm refers to a huge die with rather several 100 than a few A rating.

1 mohm + 50 V + logic level sounds unlikely.
 

Hi,

Manufacturers an distributors usually have interactive selection guides to find the desired MOSFET.

Decide if you want N or P ch alle FETs, high side or low side switching.

Klaus
 

FvM said:
The parameter combination makes no sense. 1 mohm refers to a huge die with rather several 100 than a few A rating.

1 mohm + 50 V + logic level sounds unlikely.
Click to expand...


IRLR024N
IRF7201PBf


I think this can handle 4A without heat sink, with 4.5V gate voltage 


 

I think this can handle 4A without heat sink, with 4.5V gate voltage
Click to expand...
I don't see how the statement should be related to your previous question and my answer. You have been asking for a MOSFET with a particular combination of parameters.

Or did you give up your initial specification?
 

1m ohm is wrong it's 1 ohm

I need a mosfet with can handle 4A at 4.5V gate voltage , without heat sink

- - - Updated - - -

FvM said:
I don't see how the statement should be related to your previous question and my answer. You have been asking for a MOSFET with a particular combination of parameters.

Or did you give up your initial specification?
Click to expand...

Now how to relate rise in temperature with current?
 

The design usually starts with defining acceptable power dissipation in on-state and respective Rds,on. I would choose a transistor with 15 to 30 mohm, something like Si4850.

You'll notice that the largest choice of logic level FETs is offered in SO8 package.
 

FvM said:
The design usually starts with defining acceptable power dissipation in on-state and respective Rds,on. I would choose a transistor with 15 to 30 mohm, something like Si4850.

You'll notice that the largest choice of logic level FETs is offered in SO8 package.
Click to expand...

Means, if my mosfet operate at 30V with 4A it will dissipate 120W power, 120j/sec, so I have to look for a mosfet with can handle 120W at 50C
 

Means, if my mosfet operate at 30V with 4A it will dissipate 120W power, 120j/sec, so I have to look for a mosfet with can handle 120W at 50C
Click to expand...
Not at all. Your posts suggest up to now that you're looking for a transistor operated as switch. Power dissipation in on-state is I²*Rds,on.
 

FvM said:
Not at all. Your posts suggest up to now that you're looking for a transistor operated as switch. Power dissipation in on-state is I²*Rds,on.
Click to expand...

ok means at 4A if Rds it 30mohm P= 0.48W

- - - Updated - - -

FvM said:
Not at all. Your posts suggest up to now that you're looking for a transistor operated as switch. Power dissipation in on-state is I²*Rds,on.
Click to expand...

But what if I connect 30V across drain and source , will this calculation remain same?
 

But what if I connect 30V across drain and source , will this calculation remain same?
Click to expand...
Depends on how you are operating the transistor. If you drive it into linear operation by applying a low gate voltage, it can generate high power dissipation. For dynamic power dissipation during slow switching edges, there's a safe operation area in the datasheet. Switching up to µs rise and fall time shouldn't be a problem if the repetition frequency is slow.
 
FvM said:
Depends on how you are operating the transistor. If you drive it into linear operation by applying a low gate voltage, it can generate high power dissipation. For dynamic power dissipation during slow switching edges, there's a safe operation area in the datasheet. Switching up to µs rise and fall time shouldn't be a problem if the repetition frequency is slow.
Click to expand...

That's why my MOSFET heating like hell

- - - Updated - - -

Means if I want to operate it at 4A I have to maintain 50C around it.

- - - Updated - - -

datashee not provided with CHARACTERISTICS for 30VDS
 
Last edited:

You should tell a few words about your application. "Fully on" in the initial post suggests switch operation. If it's (at least partly) linear operation, what's the load, what's the supply voltage. What's the control method?
 

supply voltage 24V, load induction(heater). I can be continuously on for 2 to 3 hour may be depend on surrounding temperature.
 

A heater would be resistive, not inductive.

And why can't it be switched on/off only (PWM mode) with low transistor powre dissipation?
 

I already told you in post 16 it's depend on surrounding temperature PWM is connected but if temperature go below limit . It should be continuously ON with 4A.
 

So it's pure switching operation and transistor power dissipation should be low in all cases.

Don't understand why you previously claimed high power dissipation.
 

FvM said:
So it's pure switching operation and transistor power dissipation should be low in all cases.

Don't understand why you previously claimed high power dissipation.
Click to expand...

SO what do you think ?
 

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