The following relay driver can use either a BJT or a MOS as a switch (of course that when using the MOS, the base resistor isnt needed).
When using a BJT, you would want the BJT to be saturated, so VCE is minimal, and therefore most of the VCC is applied to the coil.
My question deals with using a MOS as the switch.
You would also want VDS to be minimal in this case, so most the coil would take most VCC.
MOS in Linear region => RDS minimal => IDS*RDS minimal => VDS minimal
So that means that you would want the MOS to be in Linear region , right?
The thing is that i always heard that you'd want the device to be fully turned on (meaning saturated), so therefore i wanted to hear your opinion about it.
Thank you.
When using a BJT, you would want the BJT to be saturated, so VCE is minimal, and therefore most of the VCC is applied to the coil.
My question deals with using a MOS as the switch.
You would also want VDS to be minimal in this case, so most the coil would take most VCC.
MOS in Linear region => RDS minimal => IDS*RDS minimal => VDS minimal
So that means that you would want the MOS to be in Linear region , right?
The thing is that i always heard that you'd want the device to be fully turned on (meaning saturated), so therefore i wanted to hear your opinion about it.
Thank you.
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