I have an application where I want to switch on/off a resistive load (24V/300mA) from a 3.3V MCU GPIO pin at a rate of 1 HZ or slower. I also have some IRL2703 MOSFETs, and I wonder if they would do the job. Or generally, how to read a MOSFET datasheet to find out if it would do the job.
Looking at the datasheet, I find/interpret
Drain-to-Source Breakdown Voltage 30V -> sufficient for the to-be-switched 24V
RDS(on) only specified down to Vgs = 4.5V, so it does not tell me about my 3.3V.
For completeness, the Gate Threshold Voltage is min. 1V (no typ. or max. value listed), but that does not tell me if 3.3 V will work correctly.
Fig. 1 "Typical Output Characteristics" shows Id = 2A @ Vds = 24V @ Vgs = 3.0V @ Tj = 25 °C @ 20 us pulse-width
Fig. 2 "Typical Output Characteristics" shows Id = 4A @ Vds = 24V @ Vgs = 3.0V @ Tj = 175 °C @ 20 us pulse-width
I'm assuming that 20 us pulse-width refers to a PWM signal with 20 us HIGH and 20 us LOW, i.e. 50% duty cycle. Because I want to drive the MOSFET steadily, I guess that I can only drive half of Id, i.e. Id = 1A @ Tj = 25 °C.
Is my understanding correct? The graphs are typical characteristics. How do I obtain the minimum guaranteed/worst case Id?
How can I estimate the RDS(On) (and thus the dissipated power) in my setting?