If by "make" you mean create the schematic in LTspice and simulate it, then I would guess about an hour or two (mostly because this might be your first time usi

If by "make" you mean create the schematic in LTspice and simulate it, then I would guess about an hour or two (mostly because this might be your first time using LTspice). If Linear has a part that already meets those requirements, it should be a very straight forward affair.