Patent ID: 8866450

Claim:
An electronic device for DC-DC conversion comprising: a feedback loop coupled at one side to the inductor for measuring a current through the inductor by a series of an auxiliary capacitor and an auxiliary resistor; a transconductance stage coupled to the auxiliary capacitor for generating a current proportional to a voltage drop across the auxiliary capacitor, wherein the electronic device further comprises a ramp resistor coupled to the output of the transconductance stage for generating a ramp voltage across the ramp resistor and a comparator receiving at a first input the ramp voltage, wherein the output of the comparator is coupled to a gate driving stage for driving a power transistor being coupled with a control gate to the gate driving stage and with a channel to a switching node of the electronic device, wherein the transconductance stage comprises a current source coupled to a current mirror and a first transistor coupled to a first side of the current mirror and to the auxiliary capacitor and a second transistor coupled to the first side of the auxiliary capacitor and to the second side of the auxiliary capacitor and a second side of the current mirror and wherein the ramp resistor is fed with a current output from the current mirror.