Having little to no experience on MOSFETS i am having trouble part sourcing the correct one, one that will work for my applications.
But before i go with the terms let me show the circuit first
I am creating a inverted LED indicator, the initial plan was to use a 3904 instead of MOSFET, but notice R3 before the switch, the switch that i have may OFTEN HAVE a 11.3k contact resistance when closed meaning the led will remain on even if switch is closed.
Following the recommendation of a previous question and my own reading the net, I already know that i will be using a N-channel enhancement MOSFET. So i went to digikey to source possible candidates. There i was presented with filters that are way over me.
Here are the filters, Please correct me if weather i am right or wrong:
Drain to Source Voltage (Vdss) - I guess this filter means that the maximum voltage in the drain and source, basically the maximum voltage the mosfet can function.
Current - Continuous Drain (Id) @ 25°C - The maximum continuous current that the mosfet can handle. but on the choices there are some letters in parenthesis that are odd to me. e.g. 115mA*(tc)* or 115mA*(tj)* or 115mA*(ta)* . What are these ta tc tj.
Drive Voltage (Max Rds On, Min Rds On) - The voltage in the gate for the mosfet to turn on, since the mosfet act like a variable resistor the max Rds On is giving out the maximum resistance and min rds on is giving the smallest possible resistance e.g. 1.8,2.5 at below 1.8volts the mosfets is at maximum resistance and at 2.5v it is at minimum resistance
Rds On (Max) @ Id, Vgs - im a litle bit confused on this one i think this is supposed to be maximum resistance the mosfet but the values are in milli range e.g. 22mOhm @ 6.5A 4.5v
Vgs(th) (Max) @ Id - ???
Gate Charge (Qg) (Max) @ Vgs - ???
Vgs (Max) - ???
Input Capacitance (Ciss) (Max) @ Vds - ???
are there filters that i should not mind ?