Mosfet selection for switching a solenoid

[abuhafss]

Hi

I need help for the selection of suitable mosfet (TO-220 package) for switching a solenoid with following parameters:

Switching Frequency = 16 Hz
On time = 20ms
Off time = 41ms
Duty Cycle = 32.78%
Operating Voltage = 12V (for driver and solenoid)
Solenoid Inductance = 1.2mH
Current = 2.6 - 3.0A

Also the value of the gate resistor for the mosfet.

 

[KrisBlueNZ]

Do you want an N-channel or P-channel MOSFET?

What supplier?

There's a very wide range of MOSFETs that will be suitable.

Here's a list of suitable N-channel devices from Digi-Key in order of ascending price. The main difference between them is R_DSon and manufacturer.

http://www.digikey.com/product-detail/en/PSMN022-30PL,127/568-7512-5-ND/2606361
http://www.digikey.com/product-detail/en/PSMN017-30PL,127/568-9506-5-ND/3152043
http://www.digikey.com/product-detail/en/FDP8880/FDP8880FS-ND/976840
http://www.digikey.com/product-detail/en/IRFB7546PBF/IRFB7546PBF-ND/4772484
http://www.digikey.com/product-detail/en/IPP065N03L G/IPP065N03LGIN-ND/1996760

 

[abuhafss]

Thanks for your response.

Any N-Channel device from any supplier which match the parameters. I have tried 2SK1388 but it would get fairly warm. Next I am planning to try NB59N10D, IRF540, IRFZ24N, and IRFZ44 (which I already have with me).

Keeping in view the operating voltage 12V and current 3A, actually I wanted to know what RDS(on) value would be the most suitable so that the heat dissipation is minimum.

 

[BobK]

Thanks for your response.

Any N-Channel device from any supplier which match the parameters. I have tried 2SK1388 but it would get fairly warm. Next I am planning to try NB59N10D, IRF540, IRFZ24N, and IRFZ44 (which I already have with me).

Keeping in view the operating voltage 12V and current 3A, actually I wanted to know what RDS(on) value would be the most suitable so that the heat dissipation is minimum.

The lowest one.

Edit: When switching at 16Hz, the gate capacitance is not going to matter, at much higher frequencies it would.

Bob

 

[KrisBlueNZ]

Yeah, what Bob said.

A TO-220 package doesn't need heatsinking if it's dissipating less than about 0.5W. You can calculate the maximum allowable R_DSon from the power and the current:

R = P / I²
= 0.5 / 3²
= 56 mΩ

All of the devices I suggested in post #2 have R_DSon < 56 mΩ at V_GS = 10V.

 

[abuhafss]

Thanks all of you for your input.