EP4252341A1

EP4252341A1 - Power supply circuit, controlling method, lighting device driver and lighting equipment

Info

Publication number: EP4252341A1
Application number: EP21918513.9A
Authority: EP
Inventors: Jiaqi Yang; Xiongwu ZHANG; Li Zhou; Qiuxiang MAO
Original assignee: Tridonic GmbH and Co KG
Current assignee: Tridonic GmbH and Co KG
Priority date: 2021-01-15
Filing date: 2021-01-15
Publication date: 2023-10-04
Also published as: EP4252341A4; CN116711201A; WO2022151305A1

Abstract

A power supply circuit, a controlling method and a lighting equipment. an input circuit, configured to receive input power and convert the input power into a first direct current (DC) power, the input circuit comprising an input PFC (Power Factor Correction) circuit and a transformer, the input PFC circuit receiving the input power, a primary winding of the transformer being connected to the input PFC circuit, a secondary winding of the transformer outputting the first direct current power; an output regulator, configured to convert the first direct current power into a second direct current power, the second direct current power being used to drive an electric equipment; a controller, configured to output a controlling signal via an output pin according to a first detecting signal or a second detecting signal, the controlling signal being used to generate a feedback signal which is inputted to a feedback pin of a PFC chip of the PFC circuit, the first detecting signal being generated according to status of the input power, the second detecting signal being generated according to status of the output regulator, when failure status of the output regulator is detected, the PFC chip is controlled to lower down the second direct current power, when the input power is DC power, the PFC chip is controlled to lead the second direct current power into a jitter mode.

Description

POWER SUPPLY CIRCUIT, CONTROLLING METHOD, LIGHTING DEVICE DRIVER AND LIGHTING EQUIPMENT

TECHNICAL FIELD

Embodiments of the present disclosure generally relate to the field of lighting, and more particularly, to a power supply circuit, a controlling method, a lighting device driver and a lighting equipment.

BACKGROUND

This section introduces aspects that may facilitate better understanding of the present disclosure. Accordingly, the statements of this section are to be read in this light and are not to be understood as admissions about what is in the prior art or what is not in the prior art.
In the field of lighting technology, it is often needed to configure a driving current, which is used to drive a lighting device. The lighting device is LED (Light Emitting Diode) for example.
In related art, input power is input to a power supply circuit, and the power supply circuit generates direct current (DC) power. The direct current (DC) power is input to a lighting device to drive the lighting device. A dimming signal may also be input to the power supply circuit to regulate the direct current (DC) power.
The DC power can rise from minimum to maximum value according to dimming signal. DALI (Digital Addressable Lighting Interface) , NFC (Near Field Communication) , etc., may be used to regulate the DC power, thus an output power of the lighting device rises from minimum to maximum value.
The power supply circuit usually includes a PFC (Power Factor Correction) circuit. Switching frequency of a switch in the PFC circuit will be designed to around 50kHZ to 100kHZ at full load.
SUMMARY
Inventor of this disclosure found: in related art, the power supply circuit may include independent hardware to for each function, thus multiple independent hardware are needed to implement multifunction, cost of the power supply circuit could be high.
In general, embodiments of the present disclosure provide a power supply circuit, a controlling method, a lighting device driver and a lighting equipment. In the embodiments, a controller of a power supply circuit may output multiple controlling signals via a single output pin, therefore multifunction can be realized by using the single output pin, and cost of the power supply circuit could be lowered down.
In a first aspect, there is provided a power supply circuit, includes:
an input circuit, configured to receive input power and convert the input power into a first direct current (DC) power, the input circuit including an input PFC (Power Factor Correction) circuit and a transformer, the input PFC circuit receiving the input power, a primary winding of the transformer being connected to the input PFC circuit, a secondary winding of the transformer outputting the first direct current power;
an output regulator, configured to convert the first direct current power into a second direct current power, the second direct current power being used to drive an electric equipment;
a controller, configured to output a controlling signal via an output pin according to a first detecting signal or a second detecting signal, the controlling signal being used to generate a feedback signal which is inputted to a feedback pin of a PFC chip of the PFC circuit;
the first detecting signal being generated according to status of the input power, the second detecting signal being generated according to status of the output regulator, when failure status of the output regulator is detected, the PFC chip is controlled to lower down the second direct current power, when the input power is DC power, the PFC chip is controlled to lead the second direct current power into a jitter mode.
In an embodiment, when failure status of the output regulator is detected, the controlling signal outputted via the output pin is a constant level.
In an embodiment, when the controlling signal outputted via the output pin is the constant level,
a voltage on bus line that is connected between the output regulator and the secondary winding of the transformer is pulled down and kept to be lower than a shutdown level, until mains that provides the input power restarts.
In an embodiment, when the input power is DC power,
the controlling signal outputted via the output pin includes multiple groups of pulses with a predetermined interval between time adjacent groups.
In an embodiment, pulse duty cycle in each group is set as 1%～5%.
In an embodiment, the predetermined interval is set as 5～10 millisecond (ms) .
In an embodiment, the power supply circuit further includes an output trigger circuit and a first optical coupler,
the output trigger circuit is configured to receive the controlling signal, and output a driving signal to the first optical coupler,
the first optical coupler is configured to output the feedback signal to the feedback pin of the PFC chip.
In an embodiment, the power supply circuit further includes a mains detection circuit and a second optical coupler,
the mains detection circuit is configured to detect status of the input power,
the second optical coupler is configured to generate the first detecting signal according to a detecting result of the mains detection circuit, and send the first detecting signal to the controller.
In an embodiment, the power supply circuit further includes:
a control gear, configured to control the output regulator and detect status of the output regulator,
when failure status of the output regulator is detected, the control gear generates and sends the second detecting signal to the controller.
In a second aspect, there is provided a lighting device driver which includes the power supply circuit according to the first aspect of embodiment, the lighting device driver providing the second direct current (DC) power to a lighting device.
In an embodiment, the lighting device driver is an LED (Light Emitting Diode) driver.
In a third aspect, there is provided a lighting equipment, including a lighting device, and the power supply circuit according to the first aspect of embodiment, the power supply circuit providing the second direct current (DC) power to the lighting device.
In a fourth aspect, there is provided a controlling method of a power supply circuit according to the first aspect, the controlling method includes: outputting a controlling signal via an output pin according to a first detecting signal or a second detecting signal, the controlling signal being used to generate a feedback signal which is inputted to a feedback pin of a PFC chip of the PFC circuit, when failure status of the output regulator is detected, the PFC chip is controlled to stop work, when the input power is DC power, the PFC chip is controlled to lower down the second direct current power.
According to various embodiments of the present disclosure, a controller of a power supply circuit may output multiple controlling signals via a single output pin, therefore multifunction can be realized by using the single output pin, and cost of the power supply circuit could be lowered down.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and benefits of various embodiments of the disclosure will become more fully apparent, by way of example, from the following detailed description with reference to the accompanying drawings, in which like reference numerals or letters are used to designate like or equivalent elements. The drawings are illustrated for facilitating better understanding of the embodiments of the disclosure and not necessarily drawn to scale, in which:
Fig. 1 is a diagram of a power supply circuit in accordance with an embodiment of the present disclosure
Fig. 2 is a sequence chart of signals in the power supply circuit in accordance with an embodiment of the present disclosure
Fig. 3 is another sequence chart of signals in the power supply circuit in accordance with an embodiment of the present disclosure
Fig. 4 shows a flowchart of a controlling method 40 of the power supply circuit 10Fig. 1 is a diagram of a power supply circuit in accordance with an embodiment of the present disclosure.

Detailed Description

The present disclosure will now be discussed with reference to several example embodiments. It should be understood that these embodiments are discussed only for the purpose of enabling those skilled persons in the art to better understand and thus implement the present disclosure, rather than suggesting any limitations on the scope of the present disclosure.
As used herein, the terms “first” and “second” refer to different elements. The singular forms “a” and “an” are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises, ” “comprising, ” “has, ” “having, ” “includes” and/or “including” as used herein, specify the presence of stated features, elements, and/or components and the like, but do not preclude the presence or addition of one or more other features, elements, components and/or combinations thereof. The term “based on” is to be read as “based at least in part on. ” The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment. ” The term “another embodiment” is to be read as “at least one other embodiment. ” Other definitions, explicit and implicit, may be included below.
First aspect of embodiments
A power supply circuit is provided in a first embodiment.
Fig. 1 is a diagram of a power supply circuit in accordance with an embodiment of the present disclosure. As shown in Fig. 1, a power supply circuit 10 includes an input circuit 100, an output regulator 200 and a controller 300.
The input circuit 100 is configured to receive input power and convert the input power into a first direct current (DC) power. The input power may be alternating current (AC) power or direct current (DC) power. The input power may be provided by mains denoted as L (Live line) and N (Neutral line) .
As shown in Fig. 1, the input circuit 100 includes an input PFC (Power Factor Correction) circuit 110 and a transformer 120. The input PFC circuit 110 receives the input power, a primary winding P1 of the transformer 120 is connected to the input PFC circuit 110 and a secondary winding S1 of the transformer 120 outputs the first direct current power.
The output regulator 200 is configured to convert the first direct current power into a second direct current power, which is used to drive an electric equipment 20. The electric equipment 20 may be LED (Light Emitting Diode) .
In at least one embodiment, the output regulator 200 may be connected to the secondary winding S1 of the transformer 120 via a pair of bus lines denoted as Bus+ and Bus-in FIG. 1. The second direct current power may be DC voltage, which is outputted via a pair of driving pins denoted as VOUT+ and VOUT-in FIG. 1. The output regulator 200 may be buck topology. In other embodiment, the output regulator 200 may be other kind of topology, such as boost topology, etc.
The controller 300 is configured to output a controlling signal via an output pin 301 according to a first detecting signal or a second detecting signal. The controlling signal is used to generate a feedback signal which is inputted to a feedback pin 1111 of a PFC chip 111 of the PFC circuit 110. For example, the feedback pin 1111 may be a Comp pin of the PFC chip 111.
In at least one embodiment, the first detecting signal S1 may be generated according to status of the input power. For example, when the input power is DC power, the first detecting signal S1 is generated, and the output pin 301 outputs the controlling signal CS according to the first detecting signal S1, so as to control the PFC chip 111 to lead the second direct current power into a jitter mode.
In at least one embodiment, the second detecting signal S2 may be generated according to status of the output regulator. For example, when failure status of the output regulator 200 is detected, the second detecting signal S2 is generated, and the output pin 301 outputs the controlling signal CS according to the second detecting signal S2, so as to control the PFC chip 111 to lower down the second direct current power.
According to the first aspect of the embodiments, the controller of the power supply circuit outputs controlling signal with multifunction via a single output pin 301, therefore multifunction can be realized by using the single output pin, and cost of the power supply circuit could be lowered down.
In at least one embodiment, when failure status of the output regulator 200 is detected, the controlling signal CS outputted via the output pin 301 is a constant level. The constant level may be a high level or a low level. The failure status of the output regulator 200 may include over-voltage on bus lines, LED over-current on electric equipment 20, short circuit of a transistor (such as MOSFET) , etc..
Furthermore, when the controlling signal CS outputted via the output pin 301 is the constant level, a voltage on bus line (such as Bus+) will be pulled down and kept to be lower than a shutdown level, until mains that provides the input power restarts. The shutdown level may be set in the controller 300. Therefore, a latch protection is performed on the power supply circuit 10.
In at least one embodiment, when the input power is DC power, the controlling signal CS outputted via the output pin 301 may comprise multiple groups of pulses with a predetermined interval between time adjacent groups. For example, pulse duty cycle in each group is set as 1%～5%, the predetermined interval may be set as 5～10 millisecond (ms) . The pulse duty cycle and the predetermined interval may be set in the controller 300.
As shown in Fig. 1, the power supply circuit 10 further includes an output trigger circuit 400 and a first optical coupler 500. The output trigger circuit 400 is configured to receive the controlling signal, and output a driving signal to the first optical coupler 500. The first optical coupler 500 is configured to output the feedback signal FBS to the feedback pin 1111 of the PFC chip 111. For example, when the driving signal is at a high level, an LED in the first optical coupler 500 will conduct, a transistor in the first optical coupler 500 is turned on, and the feedback pin 1111 is electrically connected to ground level via the transistor in the first optical coupler 500, a feedback signal FBS of low level is sent to the feedback pin 1111.
As shown in Fig. 1, the power supply circuit 10 further includes a mains detection circuit 600 and a second optical coupler 700. The mains detection circuit 600 is configured to detect status of the input power, for example, the mains detection circuit 600 is connected to the mains. The second optical coupler 700 is configured to generate the first detecting signal according to a detecting result of the mains detection circuit, and send the first detecting signal to the controller. For example, when the input power is DC power, the mains detection circuit 600 outputs a signal with high level, and an LED in the second optical coupler 700 will conduct, a transistor in the second optical coupler 700 is turned on, the first detecting signal S1 is generated and sent to the controller 300.
As shown in Fig. 1, the power supply circuit 10 further includes a control gear 800. The control gear 800 is configured to control the output regulator 200 and detect status of the output regulator 200. When failure status of the output regulator is detected, the control gear 800 generates and sends the second detecting signal S2 to the controller.
Topology of the control gear 800 can be referred to the related art. For example, the control gear 800 may include dividing resistors to detect voltage on bus lines (such as Bus+, Bus-) , voltage or current on driving pins (such as VOUT+, VPUT-) or transistor, so as to detect over-voltage on bus lines, over-current on electric equipment 20, short circuit of a transistor (such as MOSFET) , etc.
Fig. 2 is a sequence chart of signals in the power supply circuit in accordance with an embodiment of the present disclosure. As shown in Fig. 2, failure status of the output regulator 200 is detected, and the second detecting signal S2 is generated and sent to controller 300 at T1. The controlling signal CS with high level is outputted via the output pin 301 and keeps high level from T1. The feedback signal FBS, voltage on bus line and current on driving pin VOUT+ are pulled down from T1. Voltage on bus line reaches the shutdown level at T2, and keeps lower than the shutdown level. Current on driving pin VOUT+ is pulled down to a minimum value at T2. Therefore, a latch protection is performed on the power supply circuit 10.
Fig. 3 is another sequence chart of signals in the power supply circuit in accordance with an embodiment of the present disclosure. As shown in Fig. 3, the input power is DC power, the first detecting signal S1 is generated and sent to controller 300 at T3. The controlling signal CS including multiple groups of pulses is outputted via the output pin 301 from T3. Each group includes multiple pulses (such as 5 as shown in Fig. 3) , pulse duty cycle in each group is set as 1%～5%. The predetermined interval between time adjacent groups is set as 5～10 millisecond (ms) . As shown in Fig. 3, DC current jitter is performed on the driving pin of the power supply circuit 10, i.e. the power supply circuit 10 is working under a DC jitter mode.
According to the first aspect of embodiments of the present disclosure, the following advantages can be achieved:
1. Cost saving: using one output pin 301 to achieve multi functions;
2. EMI improving: with DC jitter mode, not only jittering secondary side switching frequency, but also being helpful to jitter primary side switching frequency;
3. Convenient to implementation: just to toggle the feedback pin of primary side controller (analog or digital could be possible) . If the controller 300 is in primary, it is needed to toggle the feedback pin of secondary side.
Second aspect of embodiments
A controlling method of a power supply circuit. The power supply circuit is provided in the first aspect of embodiments. The same contents as those in the first aspect of embodiments are omitted.
Fig. 4 shows a flowchart of a controlling method 40 of the power supply circuit 10.
As shown in Fig. 4, the method 40 includes:
Block 41: when failure status of the output regulator is detected, the PFC chip is controlled to stop work, and when the input power is DC power, the PFC chip is controlled to lower down the second direct current power.
In at least one embodiment, when failure status of the output regulator is detected, the controlling signal outputted via the output pin is a constant level. When the controlling signal outputted via the output pin is the constant level, a voltage on bus line that is connected between the output regulator and the secondary winding of the transformer is pulled down and kept to be lower than a shutdown level, until mains that provides the input power restarts.
In at least one embodiment, when the input power is DC power, the controlling signal outputted via the output pin comprises multiple groups of pulses with a predetermined interval between time adjacent groups. The pulse duty cycle in each group is set as 1%～5%. The predetermined interval is set as 5～10 millisecond (ms) .
According to the first aspect of the embodiments, the controller of the power supply circuit outputs controlling signal with multifunction via a single output pin 301, therefore multifunction can be realized by using the single output pin, and cost of the power supply circuit could be lowered down.
Third aspect of embodiments
A lighting equipment is provided in an embodiment. The lighting equipment includes a power supply circuit and a lighting device. The power supply circuit is provided in the first aspect of embodiments. The lighting device maybe LED.
In the embodiment, the power supply circuit 10 (shown in Fig. 1) provides direct current (DC) power to the lighting device.
Fourth aspect of embodiments
A lighting device driver is provided in an embodiment. The lighting device driver includes the power supply circuit 10 (shown in Fig. 1) according to the first aspect of embodiments.
The lighting device driver may supply direct current (DC) power to a lighting device. The lighting device driver may be an LED driver, the lighting device may be an LED device.
An output power, output voltage or output current of the lighting device may be changed from a minimum to maximum value according to dimming signal, e.g. 1-10V, which is received via DALI (Digital Addressable Lighting Interface) , NFC (Near Field Communication) , Bluetooth etc.. Preferably the DC-DC-converter supplying the lighting device will change its output parameters (current and/or voltage) depending on the dimming signal. This change may lead to a change of loading of the power supply circuit 10 (shown in Fig. 1) .
Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable sub-combination.
Although the present disclosure has been described in language specific to structural features and/or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

A power supply circuit, comprising:

an input circuit, configured to receive input power and convert the input power into a first direct current (DC) power, the input circuit comprising an input PFC (Power Factor Correction) circuit and a transformer, the input PFC circuit receiving the input power, a primary winding of the transformer being connected to the input PFC circuit, a secondary winding of the transformer outputting the first direct current power;

an output regulator, configured to convert the first direct current power into a second direct current power, the second direct current power being used to drive an electric equipment;

a controller, configured to output a controlling signal via an output pin according to a first detecting signal or a second detecting signal, the controlling signal being used to generate a feedback signal which is inputted to a feedback pin of a PFC chip of the PFC circuit,

wherein,

the first detecting signal being generated according to status of the input power,

the second detecting signal being generated according to status of the output regulator,

when failure status of the output regulator is detected, the PFC chip is controlled to lower down the second direct current power,

when the input power is DC power, the PFC chip is controlled to lead the second direct current power into a jitter mode.
The power supply circuit according to claim 1, wherein,

when failure status of the output regulator is detected,

the controlling signal outputted via the output pin is a constant level.
The power supply circuit according to claim 2, wherein,

when the controlling signal outputted via the output pin is the constant level,

a voltage on bus line that is connected between the output regulator and the secondary winding of the transformer is pulled down and kept to be lower than a shutdown level, until mains that provides the input power restarts.
The power supply circuit according to claim 1, wherein,

when the input power is DC power,

the controlling signal outputted via the output pin comprises multiple groups of pulses with a predetermined interval between time adjacent groups.
The power supply circuit according to claim 4, wherein,

pulse duty cycle in each group is set as 1%～5%.
The power supply circuit according to claim 5, wherein,

the predetermined interval is set as 5～10 millisecond (ms) .
The power supply circuit according to claim 1, wherein,

the power supply circuit further comprises an output trigger circuit and a first optical coupler,

the output trigger circuit is configured to receive the controlling signal, and output a driving signal to the first optical coupler,

the first optical coupler is configured to output the feedback signal to the feedback pin of the PFC chip.
The power supply circuit according to claim 1, wherein,

the power supply circuit further comprises a mains detection circuit and a second optical coupler,

the mains detection circuit is configured to detect status of the input power,

the second optical coupler is configured to generate the first detecting signal according to a detecting result of the mains detection circuit, and send the first detecting signal to the controller.
The power supply circuit according to claim 1, wherein,

the power supply circuit further comprises:

a control gear, configured to control the output regulator and detect status of the output regulator,

when failure status of the output regulator is detected, the control gear generates and sends the second detecting signal to the controller.
A lighting device driver, comprising the power supply circuit according to any one of claims 1-9, wherein, the lighting device driver providing the second direct current (DC) power to a lighting device.
The lighting device driver according to claim 10, wherein,

the lighting device driver is an LED (Light Emitting Diode) driver.
A lighting equipment, comprising a lighting device, and the power supply circuit according to any one of claims 1-9, wherein,

the power supply circuit providing the second direct current (DC) power to the lighting device.
A controlling method of a power supply circuit, the power supply circuit comprising:

an input circuit, configured to receive input power and convert the input power into a first direct current (DC) power, the input circuit comprising an input PFC (Power Factor Correction) circuit and a transformer, the input PFC circuit receiving the input power, a primary winding of the transformer being connected to the input PFC circuit, a secondary winding of the transformer outputting the first direct current power;

an output regulator, configured to convert the first direct current power into a second direct current power, the second direct current power being used to drive an electric equipment;

a controller, configured to output a controlling signal via an output pin according to a first detecting signal or a second detecting signal, the controlling signal being used to generate a feedback signal which is inputted to a feedback pin of a PFC chip of the PFC circuit,

wherein,

the first detecting signal being generated according to status of the input power,

the second detecting signal being generated according to status of the output regulator,

the controlling method comprising:

when failure status of the output regulator is detected, the PFC chip is controlled to stop work,

when the input power is DC power, the PFC chip is controlled to lower down the second direct current power.