I am trying to select a proper N-Channel MOSFET for my project, but when browsing around, I look at all the different specifications for each MOSFET and am not sure how to determine my needs.
The specs I'm referring to are:
Drain-Source breakdown voltage
Gate-Source breakdown voltage
Continuous Drain Current
and Power Dissipation
In the attached file, you can see I'm using the MOSFETs as switches. A 20V+ source drives a 150mA load (each FET) and it all ends at the transistor which connects the circuit to ground.
I assume that continuous drain current would have to be my load (150mA) plus a certain percentage for a safety buffer, but I'm not sure.
I know Ohms law, but I'm not sure how to apply it to get power dissipation requirements from this, because I don't really know the voltage value to plug in.
Vds and Vgs breakdowns I'm clueless about. I mean, I'm pretty sure I understand that if a MOSFET has a Vds breakdown of 20V, I wouldn't want to exceed it, but how do I determine how high a Vds requirement I need?
As always, thanks for the advice.
EDIT: I just realized that the schematic I posted refers to the wrong microcontroller, not that it's really that important specifically which one it is, but it's supposed to be the PIC12F629.
The specs I'm referring to are:
Drain-Source breakdown voltage
Gate-Source breakdown voltage
Continuous Drain Current
and Power Dissipation
In the attached file, you can see I'm using the MOSFETs as switches. A 20V+ source drives a 150mA load (each FET) and it all ends at the transistor which connects the circuit to ground.
I assume that continuous drain current would have to be my load (150mA) plus a certain percentage for a safety buffer, but I'm not sure.
I know Ohms law, but I'm not sure how to apply it to get power dissipation requirements from this, because I don't really know the voltage value to plug in.
Vds and Vgs breakdowns I'm clueless about. I mean, I'm pretty sure I understand that if a MOSFET has a Vds breakdown of 20V, I wouldn't want to exceed it, but how do I determine how high a Vds requirement I need?
As always, thanks for the advice.
EDIT: I just realized that the schematic I posted refers to the wrong microcontroller, not that it's really that important specifically which one it is, but it's supposed to be the PIC12F629.
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