DE-112023006708-T5 - Step-down converter with dual transformers

Abstract

Systems and devices for voltage converters are described. A circuit can comprise a variety of switching elements, a first transformer, and a second transformer. The first transformer can be configured to receive an input voltage at a first voltage level. The first transformer can further be configured to reduce the input voltage to generate an output voltage based on the states of the variety of switches. The output voltage can be at a second voltage level, which is lower than the first voltage level. The second transformer can be connected in parallel to the first transformer. The second transformer can be configured to perform ripple compensation of the output voltage. The second transformer can further be configured to supply the output voltage to a load operating below the second voltage level.

Inventors

• Fei Ji
• Sheng Yuan
• Tao Xie

Assignees

• RENESAS ELECTRONICS AMERICA INC.

Dates

Publication Date

20260513

Application Date

20230720

Claims (8)

1. Circuit comprising: a plurality of switching elements; a first transformer designed to: receive an input voltage at a first voltage level; and reduce the input voltage to produce an output voltage based on the states of the plurality of switches, the output voltage being at a second voltage level lower than the first voltage level; a second transformer connected in parallel with the first transformer, the second transformer designed to: perform ripple suppression on the output voltage; and supply the output voltage to a load operating at the second voltage level.
2. Circuit according Claim 1 , where: the first transformer is a step-down transformer; and the second transformer 220 is an autotransformer.
3. Circuit according Claim 1 , wherein the transformer comprises: a first primary winding; a second primary winding; and a secondary winding, wherein the winding ratio of the first winding to the second primary winding to the secondary winding is N:N:1.
4. Circuit according Claim 3 , where a ratio of the first voltage level to the second voltage level depends on N and a duty cycle of a switching signal used to control the states of the plurality of switches.
5. Circuit according Claim 1 , wherein the second transformer is tapped at a midpoint and the winding ratio of the second transformer is 1:1.
6. Circuit according Claim 1 , whereby a connection swap of two primary windings in the first transformer allows components of the circuit to be placed on the same PCB level without intermediate layer routing.
7. Current transformer comprising: an inverter designed to receive direct current (DC) voltage and convert the DC voltage to alternating current (AC) voltage with a first voltage level; a first transformer designed to: receive AC voltage from the inverter; and reduce the AC voltage to produce an AC output voltage, the AC output voltage being at a second voltage level lower than the first voltage level; a rectifier comprising a second transformer connected in parallel with the first transformer, the rectifier being designed to receive the AC output voltage and convert the AC output voltage to a DC output voltage, and the second transformer being designed to perform ripple suppression on the DC output voltage.
8. System comprising: a controller designed to generate a control signal; a current transformer comprising: an inverter designed to receive direct current (DC) voltage and convert the DC voltage to alternating current (AC) voltage with a first voltage level; a first transformer designed to: receive AC voltage from the inverter; and use the control signal to reduce the AC voltage to generate an AC output voltage, the AC output voltage being at a second voltage level lower than the first voltage level; a rectifier comprising a second transformer connected in parallel with the first transformer, the rectifier being designed to receive the AC output voltage and convert the AC output voltage to a DC output voltage, and the second transformer being designed to perform ripple suppression on the DC output voltage.

Description

TECHNICAL AREA This disclosure generally relates to devices and equipment that include step-down converters with a dual transformer configuration. STATE OF THE ART A buck converter, also known as a step-down converter, is a DC/DC voltage converter that can convert a higher input voltage to a lower output voltage. Buck converters can be used in various applications and power supply systems to provide a stable power supply at a reduced voltage level. The buck converter may include switching elements, such as metal-oxide-semiconductor field-effect transistors (MOSFETs), which can be quickly switched on and off based on a switching signal. Control signals, such as a pulse-width modulation (PWM) signal, can be used to control the output voltage by adjusting the duty cycle of the switching signal. BRIEF DESCRIPTION OF THE DRAWINGS 1 is a diagram showing an exemplary system that can implement a step-down converter with dual transformers in one embodiment.2A is a diagram showing a step-down converter with dual transformers in one embodiment.2B is a diagram that shows a layout of the down converter from 2A in one embodiment.3A is a diagram showing a state of a double-transformer step-down converter in one embodiment.3B is a diagram showing another state of a double-transformer step-down converter in one embodiment.3C is a diagram showing another state of a double-transformer step-down converter in one embodiment.3D is a diagram showing another state of a double-transformer step-down converter in one embodiment.4 is a diagram showing current waveforms generated by implementing a double-transformer step-down converter in one embodiment.5A is a diagram showing another step-down converter with dual transformers in one embodiment.5B is a diagram showing another step-down converter with dual transformers in one embodiment.5C is a diagram showing another step-down converter with dual transformers in one embodiment.5D is a diagram showing another step-down converter with dual transformers in one embodiment.5E is a diagram showing another step-down converter with dual transformers in one embodiment.5F is a diagram showing another step-down converter with dual transformers in one embodiment.5G is a diagram showing another step-down converter with dual transformers in one embodiment.6A is a diagram showing a magnetic component with a stacked configuration in a double-transformer step-down converter in one embodiment.6B is a diagram showing a magnetic component with integrated dual transformers in a dual transformer step-down converter in one embodiment.7 is a diagram showing an exemplary implementation of a rectifier in one embodiment. DETAILED DESCRIPTION The following description sets out numerous specific details, such as certain structures, components, materials, dimensions, processing steps, and techniques, to provide an understanding of the various embodiments of the present application. However, it is understood by those skilled in the field that the various embodiments of the present application can be operated without these specific details. In other cases, known structures or processing steps have not been described in detail to avoid obscuring the present application. 1 is a diagram showing an example System 100, which includes a down converter with Dual transformers can be implemented in one embodiment. System 100 can be part of a device or machine, such as a motherboard, computer, server, vehicle, or other computing equipment and machines, comprising loads that operate with regulated voltage output by current transformers. In the 1 In the example shown, the system 100 can include a power supply 102, a controller 104, an AC/DC current transformer 106 (“AC/DC converter 106”), a buck converter 110 and at least one load, such as a load 114 and a load 116. The power supply 102 can be designed to supply power to various components in the system 100 via one or more current transformers. The power supply 102 can provide alternating current (AC current) to the AC/DC converter 106 in the form of a voltage signal, designated as AC input 120. The AC/DC converter 106 can be a power supply designed to convert the AC input 120 into a direct current (DC voltage), designated as DC voltage 126. The DC voltage 126 can be a voltage signal with a voltage level V1. The AC/DC converter 106 can supply at least one load operating at voltage level V1 with DC voltage 126. For example, the AC/DC converter 106 can supply load 116 with DC voltage 126. To power other loads operating at voltage levels different from voltage level V1, the AC/DC converter 106 can supply a DC/DC converter with DC voltage 126 to convert the DC voltage 126 to a different voltage level. For example, load 114 operates at a voltage level V2, where V2 is lower than V1. The AC/DC converter 106 can supply the buck converter 110 with DC voltage 126. The buck converter 110 can be a DC/DC current converter designed to convert DC voltage 126 to DC voltage 128. The DC voltage 1