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.
Minimum current: 500 mA
Maximum current: 15 A
Ipulse: 30 A
The MOSFET I am planning to use is the Vishay SQD50N05-11L
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.