Soft Start Circuit, review and critique requested

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josechow

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So I did a simple LTSpice simulation of a reverse polarity and soft-start setup that I would like to implement. Can anyone find any fault in the following design?

V(n002) blue = Input voltage 24v
V(n005) green = Output Voltage at the Load
I(R2) red = inrush current


M1 with D1 and R1 are the reverse polarity section, M2 with C3 D1 and R1 is the soft start section, C1/C2 are the load caps in my system to combat all the switching that goes on in the circuit to drive LED's, R4 is the expected load, R2 is just a sensing resistor so I can see the current surge of I(R2).

Capture.PNG

Any and all help is greatly appreciated. The goal is to keep the entire soft start stage pretty cheap (<$1). But if reliability becomes a concern along with board size, I suppose I am open to other suggestions. I've looked into more expensive packaged IC solutions, but they look excessive.

EDIT: Additionally, I have an inline 2A fast blow fuse to the input of M1. Circuit peak amperage during max illumination is right around 1.2A. I want to implement a soft start circuit, because my current circuit doesn't have it, and I hear an arc when I plug in the DC barrel connector, and I"ve blown the protection fuse once already. Current resolution is to plug in circuit and then plug in wal-wart, but that isn't realistic for future uses!
 
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