US 11,881,774 B2
Switching converter control loop and dynamic reference voltage adjustment
Bikash Kumar Pradhan, Bengaluru (IN); Preetam Charan Anand Tadeparthy, Bengaluru (IN); Muthusubramanian Venkateswaran, Bengaluru (IN); Venkatesh Wadeyar, Bengaluru (IN); and Siddaram Mathapathi, Bengaluru (IN)
Assigned to TEXAS INSTRUMENTS INCORPORATED, Dallas, TX (US)
Filed by TEXAS INSTRUMENTS INCORPORATED, Dallas, TX (US)
Filed on Mar. 12, 2021, as Appl. No. 17/200,564.
Prior Publication US 2022/0294344 A1, Sep. 15, 2022
Int. Cl. H02M 3/158 (2006.01); H02M 1/00 (2006.01)
CPC H02M 3/158 (2013.01) [H02M 1/00 (2013.01); H02M 1/0045 (2021.05)] 9 Claims
OG exemplary drawing
 
1. A controller, comprising:
a pulse-width modulation (PWM) circuit having a PWM control input and a PWM circuit output;
a control loop having:
a feedback input adapted to be coupled to an output terminal of a power stage;
a control loop output coupled to the PWM control input; and
a first operational amplifier with a first feedback input, a first reference input, and a first amplifier output, wherein the first feedback input is connected to the feedback input, and the first amplifier output is coupled to the PWM control input; and
a reference voltage controller configured to adjust a reference voltage provided to a reference voltage output responsive to a dynamic error estimate based on a voltage at the first amplifier output, the reference voltage controller including:
a digital-to-analog converter (DAC) having a DAC code input, a DAC reference input and a DAC output, wherein the reference voltage controller is configured to adjust a voltage applied to the DAC reference input, and the DAC output is coupled to the first reference input; and
a second operational amplifier having first and second op amp inputs and a second amplifier output, wherein the first op amp input is coupled to the DAC output, the second op amp input is coupled to the second amplifier output and the first reference input, and the dynamic error estimate accounts for error in the second operational amplifier.