US 12,206,320 B2
Adaptive inductor DCR current sensing circuit in a switching converter and associated method
Chun Shih Huang, New Taipei (CN); and Chia Chun Hsiao, New Taipei (CN)
Assigned to Chengdu Monolithic Power Systems Co., Ltd., Sichuan (CN)
Filed by Chengdu Monolithic Power Systems Co., Ltd., Chengdu (CN)
Filed on Mar. 4, 2022, as Appl. No. 17/686,853.
Claims priority of application No. 202110266737.8 (CN), filed on Mar. 11, 2021.
Prior Publication US 2022/0294330 A1, Sep. 15, 2022
Int. Cl. H02M 1/00 (2007.01); H02M 3/158 (2006.01)
CPC H02M 1/0009 (2021.05) [H02M 3/158 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A DCR current sensing circuit used in a switching converter, wherein the switching converter has a power switch and an inductor, and converts an input voltage into an output voltage, the DCR current sensing circuit comprising:
a current sensing capacitor coupled in series with a current sensing resistor to form a RC circuit, wherein the RC circuit is coupled in parallel with the inductor;
a current mirror having an input terminal, a first output terminal and a second output terminal, wherein the input terminal is configured to receive a voltage sensing signal indicative of a voltage across the current sensing capacitor, based on the voltage sensing signal, the current mirror generates a first mirror current signal at the first output terminal and a second mirror current signal at the second output terminal;
a first compensation circuit coupled to the first output terminal of the current mirror to receive the first mirror current signal and configured to generate a first current sensing signal for meeting a first requirement of the switching converter, wherein the first requirement of the switching converter comprises a transient performance requirement; and
a second compensation circuit coupled to the second output terminal of the current mirror to receive the second mirror current signal and configured to generate a second current sensing signal for meeting a second requirement of the switching converter, wherein the second requirement of the switching converter comprises a stability requirement.