Hi. I am planning to limit the current from my laptop USB port. I want to limit it to 330mA only using two mosfet and one transistor. My idea of the circuit is in the attachment. The way how I want it to work is when the the current is less than 330mA Q1 and Q2 both on but when my load draw more than 330mA then Q2 will switch off with the help of Q3 and the current to my load will be limited to 250mA only. When the current goes back to normal then Q3 will switch off and Q2 switch on again. I need your help what am I missing here.
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