Patent Application
20250105748
This application claims the benefit of CN application No. 202311266363.5, filed on Sep. 27, 2023, and incorporated herein by reference.
The present invention relates to electronic circuits, and more particularly to multi-converter switching power supplies.
Conventional solutions for multiple output power delivery (PD) adapters typically employ a two-stage design to convert an input power to an expected output power. A first stage power converter (e.g., a flyback converter or an LLC resonant converter) can convert high voltage alternating current (AC) power to lower voltage direct current (DC) power. A second stage power converter (e.g., a buck converter) can convert power output from the first stage to different DC power to meet different requirements.
However, not all outputs need to be loaded at the same time. As the number or characteristics of a load changes, power requirements also change. Multi-stage power converters capable of meeting various power requirements may be difficult to design, expensive, and/or inefficient to implement, particularly when multi-stage converters have to meet different requirements in order to be compatible with each other.
It is one of the objects of the present invention to provide an input-parallel multi-converter switching power supply.
One embodiment of the present invention discloses a multi-converter switching power supply. The multi-converter switching power supply has a first switching converter, a second switching converter, a first port, a second port, and an integrated control circuit. The first switching converter receives an input voltage, converts the input voltage to a first output voltage, and provides the first output voltage to a first output terminal and a second output terminal. The second switching converter receives the input voltage, converts the input voltage to a second output voltage, and provides the second output voltage to a third output terminal and a fourth output terminal. The second output terminal is coupled to the fourth output terminal. The first port has a first bus terminal for receiving a first voltage and a first ground terminal coupled to the second output terminal. The second port has a second bus terminal for receiving a second voltage and a second ground terminal coupled to the fourth output terminal. The integrated control circuit has a first pin, a second pin, a third pin and a switching control circuit. The first pin receives a first feedback signal representing the first output voltage. The second pin receives a second feedback signal representing the second output voltage. The third pin receives a mode signal, the mode signal controls the multi-converter switching power supply to operate in a first power supply mode or a second power supply mode. The switching control circuit controls the first switching converter and the second switching converter. When the multi-converter switching power supply operates in the first power supply mode, the first output terminal and the third output terminal are both coupled to the first bus terminal, the switching control circuit controls the first switching converter and the second switching converter to operate interleaved with each other based on the first feedback signal. When the multi-converter switching power supply operates in the second power supply mode, the first output terminal is coupled to the first bus terminal, the third output terminal is coupled to the second bus terminal, the switching control circuit is configured to control the first switching converter to provide the first voltage based on the first feedback signal, and the switching control circuit controls the second switching converter to provide the second voltage based on the second feedback signal.
Another embodiment of the present invention discloses an integrated control circuit for a multi-converter switching power supply. The integrated control circuit has a first pin, a second pin, a third pin, and a switching control circuit. The first pin receives a first feedback signal representing a first output voltage of the multi-converter switching power supply. The second pin receives a second feedback signal representing a second output voltage of the multi-converter switching power supply. The third pin receives a mode signal controlling the multi-converter switching power supply to operate in a first power supply mode or a second power supply mode. The switching control circuit controls a first switching converter and a second switching converter of the multi-converter switching power supply. When the multi-converter switching power supply operates in the first power supply mode, inputs of a first switching converter of the multi-converter switching power supply and inputs of a second switching converter of the multi-converter switching power supply are connected in parallel, and outputs of the first switching converter and outputs of the second switching converter are connected in parallel, the switching control circuit controls the first switching converter and the second switching converter to operate interleaved with each other based on the first feedback signal to provide a first voltage to a first bus terminal of a first port. When the multi-converter switching power supply operates in a second power supply mode, the inputs of the first switching converter and the inputs of the second switching converter are connected in parallel, the switching control circuit controls the first switching converter to provide the first output voltage to the first bus terminal of the first port based on the first feedback signal, the switching control circuit controls the second switching converter to provide the second output voltage to a second bus terminal of a second port based on the second feedback signal.
Yet another embodiment of the present invention discloses a control method for a multi-converter switching power supply. The control method for a multi-converter switching power supply comprises the following steps. Converting an input voltage to a first output voltage and providing the first output voltage to a first output terminal and a second output terminal. Converting the input voltage to a second output voltage and providing the second output voltage to a third output terminal and a fourth output terminal, wherein the second output terminal is coupled to the fourth output terminal. Receiving a mode signal controlling the multi-converter switching power supply to operate in a first power supply mode or a second power supply mode. In response to the multi-converter switching power supply operating in the first power supply mode, coupling both the first output terminal and the third output terminal to a first bus terminal of a first port, receiving a first feedback signal representing the first output voltage, and controlling a first switching converter of the multi-converter switching power supply and a second switching converter of the multi-converter switching power supply to operate interleaved with each other based on the first feedback signal to provide a first voltage for the first bus terminal. In response to the multi-converter switching power supply operating in the second power supply mode, coupling the first output terminal to the first bus terminal, coupling the third output terminal to a second bus terminal of a second port, receiving the first feedback signal, and receiving a second feedback signal representing the second output voltage at the same time, controlling the first switching converter to convert the input voltage to the first output voltage based on the first feedback signal, and to provide the first output voltage to the first bus terminal, and controlling the second switching converter to convert the input voltage to the second output voltage based on the second feedback signal, and to provide the second output voltage to the second bus terminal.
These and other features of the present invention will be readily apparent to persons of ordinary skill in the art upon reading the entirety of this disclosure, which comprises the accompanying drawings and claims.
The present invention can be further understood with reference to the following detailed description and the appended drawings, wherein like elements are provided with like reference numerals.
Reference will now be made in detail to the preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. While the invention will be described in conjunction with the preferred embodiments, it will be understood that they are not intended to limit the invention to these embodiments. On the contrary, the invention is intended to cover alternatives, modifications and equivalents, which may be included within the spirit and scope of the invention as defined by the appended claims. Furthermore, in the following detailed description of the present invention, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be obvious to one of ordinary skill in the art that the present invention may be practiced without these specific details. In other instances, well-known methods, procedures, components, and circuits have not been described in detail so as not to unnecessarily obscure aspects of the present invention.
In the embodiment shown in
As shown in
In one embodiment, the input capacitor Cin is configured to receive a high voltage input. In some embodiments, the high voltage input is an alternating current (AC) input, such as a line voltage. In other embodiments, the high voltage input is a high voltage direct current (DC) input, such as an EMI filtered and rectified line voltage.
In order to filter ripple and stabilize the output voltage, both output terminals of the first switching converter 101 and the second switching converter 102 are coupled to an output capacitor. As shown in
The first port USBC1 has a bus terminal BUS1 and a ground terminal RTN1, and the bus terminal BUS1 receives a first voltage V1 and the ground terminal RTN1 is coupled to ground. The second port USBC2 has a bus terminal BUS2 and a ground terminal RTN2, and the bus terminal BUS2 receives the second voltage V2 and the ground terminal RTN2 is coupled to ground. In some cases, at least one port is not connected to an external electronic device. For example, only the first port USBC1 is coupled to a first electronic device 110 and the second port USBC2 is disconnected from a second electronic device 111 (i.e., the second port USBC2 is floating). Thus, as shown in
The power delivery controller 105 is configured to control selection switches Q1 and Q2 and the load switch 104 to detect power requirements of respective ports USBC1 and USBC2 and thereby customize power outputs of the respective ports USBC1 and USBC2. In this manner, various power requirements for different numbers of loads are met. The selection switch Q1 is coupled between the first output terminal OUT1 and the bus terminal BUS1, and the selection switch Q2 is coupled between the third output terminal OUT3 and the bus terminal BUS2.
The power delivery controller 105 is coupled to the first port USBC1 and the second port USBC2 via wires 11 and 12 respectively to determine that the multi-converter switching power supply operates in a first power supply mode or a second power supply mode, and provide a mode signal MS. The first power supply mode indicates that only the first port USBC1 is coupled to the first electronic device 110 and the second port USBC2 is not coupled to the second electronic device 111. The second power supply mode indicates that the first port USBC1 is coupled to the first electronic device 110 and the second port USBC2 is coupled to the second electronic device 111. In addition, the power delivery controller 105 is coupled to the integrated control circuit 103 as well, and provides a first feedback signal VFB1 representing the first output voltage Vo1 and a second feedback signal VFB2 representing the second output voltage to the integrated control circuit 103 respectively.
The first switching converter 101 and the second switching converter 102 could have the same topology. In one embodiment, both the first switching converter 101 and the second switching converter 102 are flyback converters. Both the first switching converter 101 and the second switching converter 102 are controlled by the integrated control circuit 103. In one embodiment, the integrated control circuit 103 provides a first control signal CTRL1 and a second control signal CTRL2 to control a first switch of the first switching converter 101 and a second switch of the second switching converter 102 respectively. In another embodiment, the integrated control circuit 103 is integrated on the same chip with the first switch and the second switch.
In the embodiment shown in
When the multi-converter switching power supply 100 operates in the first power supply mode, the load switch 104 coupled between the first output terminal OUT1 and the third output terminal OUT3 is turned on, and the selection switch Q1 coupled between the first output terminal OUT1 and the bus terminal BUS1 is turned on. In this case, the first output terminal OUT1 and the third output terminal OUT3 are both coupled to the bus terminal BUS1 of the first port USBC1, and the switching control circuit 109 controls the first switching converter 101 and the second switching converter 102 to operate interleaved with each other based on the first feedback signal VFB1. So that the first switching converter 101 and the second switching converter 102 provide the first voltage V1 to the bus terminal BUS1 together. Thereby providing double current load capability to the first electronic device 110.
When the multi-converter switching power supply operates in the second power supply mode, the load switch 104 coupled between the first output terminal OUT1 and the third output terminal OUT3 is turned off, the switch Q1 coupled between the first output terminal OUT1 and the bus terminal BUS1 remains on, and the selection switch Q2 coupled between the third output terminal OUT3 and the bus terminal BUS2 is turned on. In such an embodiment, the third output terminal OUT3 is decoupled from the bus terminal BUS1 and the first output terminal OUT1. And then the third output terminal OUT3 is coupled to the bus terminal BUS2 of the second port USBC2. The switching control circuit 109 controls the first switching converter 101 to provide the first output voltage Vo1 based on the first feedback signal VFB1, in order to power the first electronic device 110. The first output voltage Vo1 is provided as the first voltage V1 supplied to the first port USBC1. At the same time, the switching control circuit 109 controls the second switching converter 102 to provide the second output voltage Vo2 based on the second feedback signal VFB2, in order to power the second electronic device 111. The second output voltage Vo2 is provided as the second voltage V2 supplied to the second port USBC2.
When detection of the first power supply mode and the second power supply mode and sensing of the first output voltage Vo1 and the second output voltage Vo2 are conducted at a secondary side of the switching converter, the isolated delivery paths are required. In some embodiments, the isolated delivery path may include an optocoupler, a transformer, a capacitive isolation device, or any other suitable electrical isolation device.
In the embodiment shown in
Similarly, when the multi-converter switching power supply 100A operates in the second power supply mode, the second feedback pin FB2 of the integrated control circuit 103 receives the second feedback signal VFB2 via the second isolated delivery path 107. The second feedback signal VFB2 is an error amplifying signal of the second output voltage Vo2. Specifically, the second isolated delivery path 107 includes a feedback resistor Rfb2, a photocoupler OC2, and a three-terminal adjustable voltage regulator device (integrated within the power delivery controller 105A as well). The photocoupler OC2 also comprises a photosensitive diode and a photosensitive transistor. When the multi-converter switching power supply 100A operates in the second power supply mode, the power delivery controller 105A provides the error amplifying signal of the second output voltage Vo2 to the second feedback pin FB2 of the integrated control circuit 103, the second feedback signal VFB2 is input to the switching control circuit 109 to control the operation of the switching control circuit.
The mode indicating pin OCH of the integrated control circuit 103 receives the mode signal MS via the third isolated delivery path 108. In the embodiment shown in
As shown in
In response to the multi-converter switching power supply 100B operating in the first power supply mode, inputs of the first switching converter 101A and inputs of the second switching converter 102A are connected in parallel, and an output of first switching converter 101A and an output of the second switching converter 102A are connected in parallel. The switching control circuit 109 is coupled to the first feedback pin FB1 and the first current sense pin CS1. The switching control circuit 109 controls the first switching converter 101A and the second switching converter 102A to operate interleaved with each other based on the first feedback signal VFB1 and a first current sense signal characterizing a current flowing through the switch S1. The first switching converter 101A and the second switching converter 102A provide the first voltage V1 to the bus terminal BUS1 of the first port USBC1. In response to the multi-converter switching power supply 100B operating in the second power supply mode, the inputs of the first switching converter 101A and the inputs of the second switching converter 102A are connected in parallel, and the output of the first switching converter 101A and the output of the second switching converter 102A are independent from each other. The switching control circuit 109 is coupled to the first feedback pin FB1 and the first current sense pin CS1, and is coupled to the second feedback pin FB2 and the second current sense pin CS2 at the same time. The switching control circuit 109 controls the first switching converter 101A to provide the first output voltage Vo1 to the bus terminal BUS1 of the first port USBC1 based on the first feedback signal VFB1 and the first current sense signal. And at the same time, the switching control circuit 109 controls the second switching converter 102A to provide the second output voltage Vo2 to the bus terminal BUS2 of the second port USBC2 based on the second feedback signal VFB2 and a second current sense signal characterizing a current flowing through the switch S2.
Although the switching converters in the embodiment of
The modulation signal generating circuit 131 is used to generate a modulation signal VM. In one embodiment, the modulation signal VM is a sawtooth wave signal. The first comparison circuit 132 has a first input terminal, a second input terminal and an output terminal. The first input terminal of the first comparison circuit 132 is coupled to the first feedback pin FB1 to receive the first feedback signal VFB1, the second input terminal of the first comparison circuit 132 is coupled to the modulation signal generating circuit 131 to receive the modulation signal VM. Based on the first feedback signal VFB1 and the modulation signal VM, the first comparison circuit 132 generates a first comparison signal PFM1 at its output terminal to control turn-on of the switch S1.
The second comparison circuit 133 has a first input terminal, a second input terminal and an output terminal. The first input terminal of the second comparison circuit 133 receives the first current sense signal representing the current flowing through the switch S1, the second input terminal of the second comparison circuit 133 receives a first threshold signal Ipk_ref1. Based on the first current sense signal and the first threshold signal Ipk_ref1, the second comparison circuit 133 generates a second comparison signal PR at its output terminal to control turn-off of the switch S1. In one embodiment, the first threshold signal Ipk_ref1 is related to the first feedback signal VFB1. The integrated control circuit 103B further comprises a current threshold generating circuit 130 coupled to the first feedback pin FB1, the current threshold generating circuit 130 generates the first threshold signal Ipk_ref1 based on the first feedback signal VFB1.
The first logic circuit 134 has a first input terminal, a second input terminal and an output terminal. The first input terminal of the first logic circuit 134 is coupled to the first comparison circuit 132 to receive the first comparison signal PFM1, the second input terminal of the first logic circuit 134 is coupled to the second comparison circuit 133 to receive the second comparison signal PR. Based on the first comparison signal PFM1 and the second comparison signal PR, the first logic circuit 134 generates the first control signal CTRL1 of the switch S1 at the output terminal and outputs the control signal CTRL1 at the first driving terminal DRV1.
Similarly, the third comparison circuit 135 has a first input terminal, a second input terminal and an output terminal. The first input terminal of the third comparison circuit 135 is coupled to the second feedback pin FB2 to receive the second feedback signal VFB2, the second input terminal of the third comparison circuit 135 is coupled to the modulation signal generating circuit 131 to receive the modulation signal VM. Based on the second feedback signal VFB2 and the modulation signal VM, the third comparison circuit 135 generates a third comparison signal PFM2 at its output terminal to control turn-on of the switch S2 in the second power supply mode.
The phase shift control circuit 136 receives the first control signal CTRL1, performs phase shifting based on the first control signal CTRL1, and generates a phase shift control signal CTRLD to control the turn-on of the switch S2 in the first power supply mode. The time period required for the switch S1 to perform a complete switching action can be defined as one period. The phase shift control circuit 136 may turn on the switch S2 a half period after the switch S1 is turned on.
The selection circuit 137 is coupled to the third feedback pin OCH to receive the mode signal MS. The selection circuit 137 selects one of the phase shift control signal CTRLD output by the phase shift control circuit 136 and the third comparison signal PFM2 output by the third comparison circuit 135 as a conduction control signal FS in response to the mode signal MS.
The fourth comparison circuit 138 has a first input terminal, a second input terminal and an output terminal. The first input terminal of the fourth comparison circuit 138 receives the second current sense signal representing the current flowing through the switch S2, the second input terminal fourth comparison circuit 138 receives a second threshold signal Ipk_ref2. The integrated control circuit 103B further comprises a current threshold generating circuit 140 coupled to the second feedback pin FB2. The current threshold generating circuit 140 generates a threshold signal Ipk_ref0 based on the second feedback signal VFB2. The selection circuit 141 is used to select the first threshold signal Ipk_ref1 or the threshold signal Ipk_ref0 as the second threshold signal Ipk_ref2 in different modes and to provide the second threshold signal Ipk_ref2 to the output terminal. Specifically, in the first power supply mode, the second threshold signal Ipk_ref2 is the same as the first threshold signal Ipk_ref1. In the second power supply mode, the second threshold signal Ipk_ref2 is the threshold signal Ipk_ref0 related to the second feedback signal VFB2. The threshold signal Ipk_ref0 is generated by the current threshold generating circuit 140 based on the second feedback signal VFB2. Based on the second current sense signal and the second threshold signal Ipk_ref2, the fourth comparison circuit 138 generates a fourth comparison signal FR at the output terminal to control turn-off of the switch S2. To maintain system stability, the second comparison circuit 133 and the fourth comparison circuit 138 often introduced with slope compensation signals, such as signals RAMP1 and RAMP2 shown in
The second logic circuit 139 has a first input terminal, a second input terminal and an output terminal. The first input terminal of the second logic circuit 139 is coupled to the selection circuit 137 to receive the selected conduction control signal FS, the second input terminal of the second logic circuit 139 is coupled to the fourth comparison circuit 138 to receive the fourth comparison signal FR. Based on the conduction control signal FS and the fourth comparison signal FR, the second logic circuit 139 generates the second control signal CTRL2 at the output terminal to control the switch S2.
At the step 701, converting the input voltage to the first output voltage and providing the first output voltage to a first output terminal and a second output terminal. The first output capacitor is coupled between the first output terminal and the second output terminal.
At the step 702, converting the input voltage to the second output voltage and providing the second output voltage to a third output terminal and a fourth output terminal. The second output terminal is coupled to the fourth output terminal, and the second output capacitor is coupled between the third output terminal and the fourth output terminal.
At the step 703, receiving a mode signal controlling the multi-converter switching power supply to operate in a first power supply mode or a second power supply mode in response to the multi-converter switching power supply operates in the first power supply mode, entering steps 704 to 706. In response to the multi-converter switching power supply operates in the second power supply mode, entering steps 707 to 709.
In one embodiment, when the multi-converter switching power supply operates in the first power supply mode, only a first port is coupled to a first electronic device, and when the multi-converter switching power supply operates in a second power supply mode, the first port is coupled to the first electronic device while the second port is coupled to a second electronic device.
At the step 704, coupling both the first output terminal and the third output terminal to a bus terminal of the first port.
At the step 705, receiving a first feedback signal representing the first output voltage.
At the step 706, controlling the first switching converter and the second switching converter to operate interleaved with each other based on the first feedback signal and to provide a first voltage to the bus terminal of the first port.
At the step 707, in response to the multi-converter switching power supply is operating in the second power supply mode, coupling the first output terminal to the bus terminal of the first port, and coupling the third output terminal to a bus terminal of the second port.
At the step 708, receiving the first feedback signal, and receiving the second feedback signal representing the second output voltage at the same time.
At the step 709, controlling the first switching converter based on the first feedback signal to convert the input voltage to the first output voltage, and to provide the first output voltage to the bus terminal of the first port. Controlling the second switching converter based on the second feedback signal to convert the input voltage to the second output voltage, and to provide the second output voltage to the bus terminal of the second port.
In an embodiment of the present invention, when only the first port is coupled to the first electronic device, the first switching converter and the second switching converter are automatically configured to operate interleaved with each other, providing double load capacity to the first electronic device, so that the power supply requirements of the high power load can be satisfied. When the second port is further coupled to the second electronic device, the first switching converter and the second switching converter are reconfigured to have their inputs connected in parallel and their outputs independent from each other to provide corresponding output voltages for the first electronic device and the second electronic device respectively, in order to meet the power supply requirements of multiple loads.
Obviously many modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described. It should be understood, of course, the foregoing disclosure relates only to a preferred embodiment (or embodiments) of the invention and that numerous modifications may be made therein without departing from the spirit and the scope of the invention as set forth in the appended claims. Various modifications are contemplated and they obviously will be resorted to by those skilled in the art without departing from the spirit and the scope of the invention as hereinafter defined by the appended claims as only a preferred embodiment(s) thereof has been disclosed.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202311266363.5 | Sep 2023 | CN | national |
