Electronics › Electronics › difference between two transistors › Hi, Chalani. Good
May 6, 2013 at 9:32 pm
#9651
Participant
Hi, Chalani.
Good question.
Generally, a logic device is on or off, whereas a standard mosfet acts
as a variable resistor (between the drain and gate).
A general purpose mosfet gate may have a range (4-6) volts to saturate,
this may be a problem when driving with ttl or cmos logic (4.8 – 5v supply)
It may not have sufficient gate voltage to saturate or completely turn on.
(if you are driving a relay or solenoid = possible device overheating)
By using a logic version mosfet, you will get full saturation at logic level.
Of course, You must still consult the datasheet to see of both TTL or CMOS levels are supported.