KeepItSimpleStupid
- Joined Mar 4, 2014
- 5,088
if your looking for a single number, you won't find it. You really should look at figure #9. Why figure #9?
It gives you an idea of Rds(ON) and junction temp as a function of Vgs
But yes, your right the max values of Vgs is where damage starts to occur. Same for some of the other maximums.
Vt is where the FET STARTS to conduct, but it isn't fully on yet. We can see from that datasheet that operating somewhere between 5 and 10 v and 100 mA is a good place for a switch.
Good numbers of Vgs are between 5 and 10V when operating as a switch.
Your actual load (Say it was a 10 mA LED) can change these numbers.
In terms of Vgs min, typ and max are really places when you want the part to behave in all cases. When designing a current limiting resistor for a LED, you should use Vf (max) when you look at the high end. So a 2.1 V led and a 0.7 V diode drop might take you to 2.8 V and suppose you have a 3.3. V +-10% supply?
Numbers don't tell all. You sometimes have to look at the graphs. The numbers HELP select.
It gives you an idea of Rds(ON) and junction temp as a function of Vgs
But yes, your right the max values of Vgs is where damage starts to occur. Same for some of the other maximums.
Vt is where the FET STARTS to conduct, but it isn't fully on yet. We can see from that datasheet that operating somewhere between 5 and 10 v and 100 mA is a good place for a switch.
Good numbers of Vgs are between 5 and 10V when operating as a switch.
Your actual load (Say it was a 10 mA LED) can change these numbers.
In terms of Vgs min, typ and max are really places when you want the part to behave in all cases. When designing a current limiting resistor for a LED, you should use Vf (max) when you look at the high end. So a 2.1 V led and a 0.7 V diode drop might take you to 2.8 V and suppose you have a 3.3. V +-10% supply?
Numbers don't tell all. You sometimes have to look at the graphs. The numbers HELP select.