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Fixed the question formation - missing auxiliary (or helping) verb - see e.g. <https://www.youtube.com/watch?v=t4yWEt0OSpg&t=1m49s> (QUASM). Copy edited (e.g. ref. <https://en.wikipedia.org/wiki/Lithium-ion_battery>). Added the missing units in the calculation.
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edit approved Apr 1, 2020 at 18:12
Peter Mortensen
edit approved Apr 1, 2020 at 18:12
Peter Mortensen
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How tocan I choose a MOSFET based on Rds? I have understood all the parameters except this

I have understood all the parameters except RdsRds and conduction loss. Please explain them to me.

I am using a Lithiumlithium-Ionion battery pack of 36 V and its maximum voltage is 42 V to drive a motor.

Motor specsspecifications:
  
minimumMinimum current  : 500 mA
  
maximumMaximum current  : 15 A
Ipulse
Ipulse: 30 A

The MOSFET I am planning to use is the Vishay SQD50N05-11L

MOSFET specsspecifications:

MOSFET specifications part 1

MOSFET specifications part 2

So based on the above specification, I have calculated the power dissipation:

Power dissipation: (i)^2I2 * Rds --->Rds = (15A15 A)^22 * 11 mohm = 2.47 watts

andAnd the maximum power the transistor can dissipate without a heat sink:

T(max)Tmax - T(ambientambient) / R(jA) = ---> 175(175 °C - 25 °C) / 60 °C/W = 2.5 watt

I am confused that how to check and relate the Power dissipation with Rds and select the MOSFET based on it.
Is the MOSFET that I have chosen okay, based on the above specs or should I go for a MOSFET with low Rds? And please explain how to select the MOSFETs based on Rds I am confused that how to check and relate the power dissipation with Rds and select the MOSFET based on it. Is the MOSFET that I have chosen okay, based on the above specifications or should I go for a MOSFET with a low Rds?

And please explain how to select the MOSFETs based on Rds.

How to choose MOSFET based on Rds? I have understood all the parameters except this

I have understood all the parameters except Rds and conduction loss. Please explain them to me.

I am using a Lithium-Ion battery pack of 36 V and its maximum voltage is 42 V to drive a motor.

Motor specs:
  minimum current  : 500 mA
  maximum current  : 15 A
Ipulse : 30 A

The MOSFET I am planning to use is the Vishay SQD50N05-11L

MOSFET specs:

MOSFET specifications part 1

MOSFET specifications part 2

So based on the above specification, I have calculated the power dissipation:

Power dissipation: (i)^2 * Rds ---> (15A)^2 * 11 mohm = 2.47 watts

and the maximum power the transistor can dissipate without heat sink:

T(max) - T(ambient) / R(jA) ---> 175 - 25 / 60 = 2.5 watt

I am confused that how to check and relate the Power dissipation with Rds and select the MOSFET based on it.
Is the MOSFET that I have chosen okay, based on the above specs or should I go for a MOSFET with low Rds? And please explain how to select the MOSFETs based on Rds

How can I choose a MOSFET based on Rds? I have understood all the parameters except this

I have understood all the parameters except Rds and conduction loss. Please explain them to me.

I am using a lithium-ion battery pack of 36 V and its maximum voltage is 42 V to drive a motor.

Motor specifications: 
Minimum current: 500 mA 
Maximum current: 15 A
Ipulse: 30 A

The MOSFET I am planning to use is the Vishay SQD50N05-11L

MOSFET specifications:

MOSFET specifications part 1

MOSFET specifications part 2

So based on the above specification, I have calculated the power dissipation:

Power dissipation: I2 * Rds = (15 A)2 * 11 mohm = 2.47 watts

And the maximum power the transistor can dissipate without a heat sink:

(Tmax - Tambient) / R(jA) = (175 °C - 25 °C) / 60 °C/W = 2.5 watt

I am confused that how to check and relate the power dissipation with Rds and select the MOSFET based on it. Is the MOSFET that I have chosen okay, based on the above specifications or should I go for a MOSFET with a low Rds?

And please explain how to select the MOSFETs based on Rds.

Became Hot Network Question
Removed signature per site rules: https://electronics.stackexchange.com/help/behavior | Light copy edit for readability and ISO 1000 presentation. Added link to MOSFET datasheet.
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SamGibson ♦
SamGibson ♦
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How to choose Mosfet BasedMOSFET based on Rds  ? iI have understood all the parameters except so kindly explain?this

I have understood all the parameters except Rds and conduction Loss kindlyloss. Please explain them to me.

iI am usingusing a Lithium Ion Battery Pack-Ion battery pack of 36v36 V and its Maximum Voltagemaximum voltage is 42V42 V to drive a motor.

Motor specs: 
minimum current : 500 mA 
maximum current : 15 A 
Ipulse : 30A30 A

The MOSFET iI am planning to use is SQD50N05-11Lthe Vishay SQD50N05-11L

MOSFET Specsspecs:   

enter image description hereMOSFET specifications part 1

enter image description hereMOSFET specifications part 2

SOSo based on Above Specification ithe above specification, I have calculated the Power Dissipation power dissipation:

Power dissipation: (i)^2 * Rds ---> (15A)^2 * 11 mohm = 2.47 watts

and Maximumthe maximum power the Transistortransistor can dissipate without dissipate without heat sink:

T(max) - T(ambient) / R(jA) ---> 175 - 25 / 60 = 2.5 watt

I am confused that how to check and relate the Power dissipation with Rds and select the MOSFET Basedbased on it.
Is the MOSFET that iI have chosen is okay, based on the above specs or should iI go for a MOSFET with low Rds . and kidnly? And please explain how to select the MOSFETSMOSFETs based on Rds

Regards, Muthukumar

How to choose Mosfet Based on Rds  ? i have understood all the parameters except so kindly explain?

I have understood all the parameters except Rds and conduction Loss kindly explain me.

i am using a Lithium Ion Battery Pack of 36v and its Maximum Voltage is 42V to drive a motor

Motor specs: minimum current : 500 mA maximum current : 15 A Ipulse : 30A

The MOSFET i am planning to use is SQD50N05-11L

MOSFET Specs:  enter image description here

enter image description here

SO based on Above Specification i have calculated the Power Dissipation :

Power dissipation: (i)^2 * Rds ---> (15A)^2 * 11 mohm = 2.47 watts

and Maximum power the Transistor can dissipate without dissipate without heat sink

T(max) - T(ambient) / R(jA) ---> 175 - 25 / 60 = 2.5 watt

I am confused that how to check and relate the Power dissipation with Rds and select the MOSFET Based on it Is the MOSFET that i have chosen is okay based on the above specs or should i go for a MOSFET with low Rds . and kidnly explain how to select the MOSFETS based on Rds

Regards, Muthukumar

How to choose MOSFET based on Rds? I have understood all the parameters except this

I have understood all the parameters except Rds and conduction loss. Please explain them to me.

I am using a Lithium-Ion battery pack of 36 V and its maximum voltage is 42 V to drive a motor.

Motor specs: 
minimum current : 500 mA 
maximum current : 15 A 
Ipulse : 30 A

The MOSFET I am planning to use is the Vishay SQD50N05-11L

MOSFET specs: 

MOSFET specifications part 1

MOSFET specifications part 2

So based on the above specification, I have calculated the power dissipation:

Power dissipation: (i)^2 * Rds ---> (15A)^2 * 11 mohm = 2.47 watts

and the maximum power the transistor can dissipate without heat sink:

T(max) - T(ambient) / R(jA) ---> 175 - 25 / 60 = 2.5 watt

I am confused that how to check and relate the Power dissipation with Rds and select the MOSFET based on it.
Is the MOSFET that I have chosen okay, based on the above specs or should I go for a MOSFET with low Rds? And please explain how to select the MOSFETs based on Rds

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Muthu
Muthu
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How to choose Mosfet Based on Rds ? i have understood all the parameters except so kindly explain?

I have understood all the parameters except Rds and conduction Loss kindly explain me.

i am using a Lithium Ion Battery Pack of 36v and its Maximum Voltage is 42V to drive a motor

Motor specs: minimum current : 500 mA maximum current : 15 A Ipulse : 30A

The MOSFET i am planning to use is SQD50N05-11L

MOSFET Specs: enter image description here

enter image description here

SO based on Above Specification i have calculated the Power Dissipation :

Power dissipation: (i)^2 * Rds ---> (15A)^2 * 11 mohm = 2.47 watts

and Maximum power the Transistor can dissipate without dissipate without heat sink

T(max) - T(ambient) / R(jA) ---> 175 - 25 / 60 = 2.5 watt

I am confused that how to check and relate the Power dissipation with Rds and select the MOSFET Based on it Is the MOSFET that i have chosen is okay based on the above specs or should i go for a MOSFET with low Rds . and kidnly explain how to select the MOSFETS based on Rds

Regards, Muthukumar