Cicero
Active Member
Hi guys,
I'm trying to use an IRF540 (**broken link removed**) as a sort of "soft-start" switch for particular piece of equipment with high inrush and high load capacitance properties.
So essentially I'm just ramping the voltage up 'slowly', the time scale for this I haven't bedded down. But I'm thinking around 600ms to 1500ms from 'off' to fully 'on'.
My specs are:
Vin = 55V
Inominal = 2A
With the ramp up in voltage, the current slowly ramps as well, this has potential for a lot of heat and I could blow my FET if I'm not careful and keep the junction below the max temperature.
With that timescale of ramping, how do you work out the power and heat dissipated to make sure I keep my junction at a decent temperature? Is 600ms+ ramp time even considered a transient response?
I'm trying to use an IRF540 (**broken link removed**) as a sort of "soft-start" switch for particular piece of equipment with high inrush and high load capacitance properties.
So essentially I'm just ramping the voltage up 'slowly', the time scale for this I haven't bedded down. But I'm thinking around 600ms to 1500ms from 'off' to fully 'on'.
My specs are:
Vin = 55V
Inominal = 2A
With the ramp up in voltage, the current slowly ramps as well, this has potential for a lot of heat and I could blow my FET if I'm not careful and keep the junction below the max temperature.
With that timescale of ramping, how do you work out the power and heat dissipated to make sure I keep my junction at a decent temperature? Is 600ms+ ramp time even considered a transient response?