US 12,334,811 B2
Closed loop stability ramp implementation for Constant On-Time buck converter
Niccolo′ Brambilla, San Donato Milanese (IT); Sandro Rossi, Pavia (IT); Valeria Bottarel, Novara (IT); Stefano Corona, Borgarello (IT); and Fulvio Ottavio Lissoni, Cusago (IT)
Assigned to STMICROELECTRONICS INTERNATIONAL N.V., Geneva (CH)
Filed by STMicroelectronics International N.V., Geneva (CH)
Filed on Jun. 14, 2023, as Appl. No. 18/334,757.
Prior Publication US 2024/0421691 A1, Dec. 19, 2024
Int. Cl. H02M 1/088 (2006.01); H02M 3/157 (2006.01); H02M 3/158 (2006.01); H03L 7/08 (2006.01)
CPC H02M 1/088 (2013.01) [H02M 3/157 (2013.01); H02M 3/158 (2013.01); H03L 7/08 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A switched-mode power supply (SMPS) comprising:
a Buck converter; and
a control circuit for the Buck converter, comprising:
a comparator configured to compare a feedback voltage of the Buck converter with a compensation ramp voltage;
a pulse generator coupled to an output terminal of the comparator and configured to generate a pulse signal in response to a rising edge in an output signal of the comparator, wherein switching of the Buck converter is controlled by the pulse signal;
a transconductance amplifier, wherein a first input terminal of the transconductance amplifier is configured to receive the feedback voltage, and a second input terminal of the transconductance amplifier is configured to receive a reference voltage;
a first capacitor coupled between an output terminal of the transconductance amplifier and a reference voltage node; and
a ramp signal generator configured to generate a ramp voltage and add the ramp voltage to a first voltage at the output terminal of the transconductance amplifier to generate the compensation ramp voltage, wherein the ramp voltage is a linear voltage signal, and a gradient of the linear voltage signal is proportional to a switching frequency of the Buck converter.