The schematic is made by Great scott (a YouTuber).I need to know can we add a current limit to it by using a sense resistor and feeding the sensed voltage proportional to the current in the feedback controller opamp?
My question is can I add the output of this current limit part to the voltage feedback controller opamp?(in the inverting input)?
Electrical – Current limit in boost converter
boost
Best Answer
With this topology, it's not possible to implement a current limit. See the current path? It's from the Vcc power source through L1 and D1 into the load.
There is no switched element in that path.
To add a current limit, you'd had to add a switch in the current path. Because a conducting MOSFET has lower losses than a diode, it is adviseable to put another MOSFET in instead of the diode D1.
simulate this circuit – Schematic created using CircuitLab
The path over R_limit and the diode is for preventing T1 and/or T2 to be shot by overvoltage if T1 is opened while current is flowing through L1 and T2 is not opened because of the current limiting function.