US 12,081,121 B2
Audio electronic system with switching converter
Edoardo Botti, Vigevano (IT)
Assigned to STMicroelectronics S.r.l., Agrate Brianza (IT)
Filed by STMicroelectronics S.r.l., Agrate Brianza (IT)
Filed on May 2, 2023, as Appl. No. 18/310,824.
Application 18/310,824 is a division of application No. 17/313,505, filed on May 6, 2021, granted, now 11,671,009.
Claims priority of application No. 102020000015232 (IT), filed on Jun. 24, 2020.
Prior Publication US 2023/0268830 A1, Aug. 24, 2023
Int. Cl. H02M 3/158 (2006.01); H02M 3/155 (2006.01); H03F 3/217 (2006.01); H04R 3/04 (2006.01)
CPC H02M 3/155 (2013.01) [H03F 3/217 (2013.01); H04R 3/04 (2013.01); H03F 2200/03 (2013.01)] 18 Claims
OG exemplary drawing
 
1. An audio electronic system comprising:
a loop filter configured to receive and filter an input audio signal;
a pulse-width modulator (PWM) and controller coupled to the loop filter and configured to:
receive the filtered input audio signal; and
control a switching converter;
a battery configured to provide a DC input voltage;
the switching converter, coupled to the battery and to the PWM and controller, the switching converter comprising:
first and second Zeta converters having respective output terminals configured to be connected across a load, each the first and second Zeta converters comprising:
an output stage comprising a respective output inductor, and configured to provide a respective DC output voltage to the load;
a first switching stage configured to be switched between a first state in which the DC input voltage is allowed to be provided to an input stage, and a second state in which the DC input voltage is prevented from being provided to the input stage;
a second switching stage configured to be switched between the first state in which a reference voltage is allowed to be provided to the output stage, and the second state in which the reference voltage is prevented from being provided to the output stage; and
the input stage, configured to receive the DC input voltage and comprising an input inductor having a first terminal electrically coupled to the first switching stage;
wherein the input inductors of the input stages of the first and second Zeta converters are magnetically coupled to each other such that in response to a first current entering the first terminal of the input inductor of the first Zeta converter that is coupled to the first switching stage of the first Zeta converter, a first voltage induced by the first current is positive at the first terminal of the input inductor of the second Zeta converter that is coupled to the first switching stage of the second Zeta converter; and
wherein the output inductors of the output stages of the first and second Zeta converters are magnetically coupled to each other such that in response to a second current entering a terminal of the output inductor of the first Zeta converter that is coupled to the output terminal of the first Zeta converter, a second voltage induced by the second current is positive at the terminal of the output inductor that is coupled to the output terminal of the second Zeta converter; and
a loudspeaker coupled to the output stages of the first and second Zeta converters and configured to be driven by the respective DC output voltages.