US-20260128915-A1 - ETHERNET POWER SOURCE EQUIPMENT, STEP-DOWN CONTROL CIRCUIT, AND METHOD OF CONTROLLING THE SAME

US20260128915A1US 20260128915 A1US20260128915 A1US 20260128915A1US-20260128915-A1

Abstract

An Ethernet power source equipment (PSE) is coupled to a load device, and the Ethernet PSE includes a power supply device, an output control circuit, a path control circuit, and a control module. When the output control circuit detects that the load device is not coupled to an output terminal of the Ethernet PSE, the path control circuit disconnects a power supplying path between the output terminal to the control module, and the output control circuit adjusts an output voltage to a first voltage so that the control module enters a disabled state. When the output control circuit detects that the load device is coupled to the output terminal, the path control circuit short-circuits the power supplying path, and the output control circuit adjusts the output voltage to a second voltage so that the control module enters an enabled state.

Inventors

Kuan-Hsien Tu
Cheng-Chieh Lee
CHENG-EN LIU
Hsuan-Chen LIN

Assignees

DELTA ELECTRONICS, INC.

Dates

Publication Date: 20260507
Application Date: 20250224
Priority Date: 20241104

Claims (16)

1 . An Ethernet power source equipment configured to couple to a load device, and the Ethernet power source equipment comprising: a power supply device, configured to convert an input voltage into an output voltage, and provide the output voltage to the load device through an output terminal, an output control circuit, coupled to the output terminal, and configured to adjust the output voltage to a first voltage or a second voltage based on whether the load device is coupled to the output terminal, a path control circuit, coupled to the output terminal, and a control module, coupled to the path control circuit, wherein when the output control circuit is configured to detect that the load device is not coupled to the output terminal, the path control circuit is configured to disconnect a power supplying path between the output terminal and the control module, and the output control circuit is configured to adjust the output voltage to the first voltage so that the control module enters a disabled state; when the output control circuit is configured to detect that the load device is coupled to the output terminal, the path control circuit is configured to connect the power supplying path, and the output control circuit is configured to adjust the output voltage to the second voltage so that the control module enters an enabled state.
2 . The Ethernet power source equipment as claimed in claim 1 , wherein the output control circuit comprises: a voltage dividing circuit, coupled to a first end of the output terminal, and configured to provide an impedance according to a potential of the first end, and a voltage regulating circuit, coupled to a second end of the output terminal and the voltage dividing circuit, and configured to adjust the output voltage according to the impedance, wherein the voltage dividing circuit is configured to provide a first impedance according to the load device not being coupled to the power supply device and the potential of the first end being in a first potential, and the voltage regulating circuit is configured to adjust the output voltage to the first voltage according to the first impedance; the voltage dividing circuit is configured to provide a second impedance according to the load device being coupled to the power supply device, and the voltage regulating circuit is configured to adjust the output voltage to the second voltage according to the second impedance.
3 . The Ethernet power source equipment as claimed in claim 2 , wherein the voltage dividing circuit comprises: a first voltage dividing circuit, comprising a plurality of resistors coupled in series, and the voltage regulating circuit coupled to a node formed between two resistors, a second voltage dividing circuit, coupled to the plurality of resistors in series, and an impedance control circuit, coupled to the second voltage dividing circuit in parallel, and the impedance control circuit configured to selectively bypass the second voltage dividing circuit so that the voltage dividing circuit is configured to provide the first impedance or the second impedance, wherein the impedance control circuit is configured to not bypass the second voltage dividing circuit to provide the first impedance according to the load device not being coupled to the power supply device and the potential of the first end being in the first potential; the impedance control circuit is configured to bypass the second voltage dividing circuit to provide the second impedance according to the load device being coupled to the power supply device.
4 . The Ethernet power source equipment as claimed in claim 2 , wherein the output control circuit further comprises: a feedback circuit, coupled to the voltage regulating circuit, wherein the voltage regulating circuit is configured to adjust a feedback signal of the feedback circuit to a first feedback signal according to the first impedance, and the power supply device is configured to adjust the output voltage to the first voltage according to the first feedback signal; the voltage regulating circuit is configured to adjust the feedback signal to a second feedback signal according to the second impedance, and the power supply device is configured to adjust the output voltage to the second voltage according to the second feedback signal.
5 . The Ethernet power source equipment as claimed in claim 2 , wherein the output control circuit further comprises: a clamping circuit, coupled to the voltage regulating circuit and the second end, wherein the clamping circuit is configured to provide a clamping voltage according to the load device being coupled to the power supply device so that a voltage between the second end and a ground terminal is equal to the sum of a regulated voltage of the voltage regulating circuit and the clamping voltage.
6 . The Ethernet power source equipment as claimed in claim 5 , wherein the clamping circuit comprises: a clamping component, coupled to the voltage regulating circuit and the second end, and the clamping component configured to provide the clamping voltage, and a bypass circuit, coupled to the clamping component in parallel, wherein the bypass circuit is configured to bypass the clamping component and not to provide the clamping voltage according to the load device not being coupled to the power supply device and the potential of the first end is in the first potential.
7 . The Ethernet power source equipment as claimed in claim 2 , wherein the path control circuit is further coupled to the output control circuit; the voltage dividing circuit is configured to provide the first impedance when the potential of the first end is in the first potential and the path control circuit is configured to provide a first path voltage to the output control circuit.
8 . The Ethernet power source equipment as claimed in claim 7 , wherein the voltage dividing circuit is configured to provide the second impedance when the potential of the first end is a second potential or the path control circuit is configured to provide a second path voltage to the output control circuit.
9 . A step-down control circuit applied to an Ethernet power source equipment, the Ethernet power source equipment comprising a power supply device configured to provide an output voltage through a first end and a second end, and the power supply device comprising a feedback control circuit; the feedback control circuit comprising a clamping component coupled to the second end of the power supply device in series, a feedback circuit, a voltage regulating circuit, and a first voltage dividing circuit coupled to the second end and the voltage regulating circuit, the step-down control circuit comprising: a second voltage dividing circuit, coupled to the first voltage dividing circuit in series, an impedance control circuit, coupled to the second voltage dividing circuit in parallel and coupled to the first end, and the impedance control circuit configured to selectively bypass the second voltage dividing circuit to provide a first impedance or a second impedance to the voltage regulating circuit, and a bypass circuit, coupled to the first end and coupled to the clamping component in parallel, wherein a power pin of a controller of the Ethernet power source equipment is coupled to the impedance control circuit and the bypass circuit; when a potential of the first end is in a first potential, and a power supplying path between the second end and the power pin is disconnected to provide a first path voltage to the impedance control circuit, the impedance control circuit is configured not to bypass the second voltage dividing circuit to provide the first impedance to the voltage regulating circuit, and the bypass circuit is configured to bypass the clamping component so that the feedback circuit is configured to notify the power supply device to step down the output voltage to a first voltage according to the first impedance.
10 . The step-down control circuit as claimed in claim 9 , wherein when the potential of the first end is in a second potential, or the power supplying path is short-circuited to provide a second path voltage to the impedance control circuit, the impedance control circuit is configured to bypass the second voltage dividing circuit to provide the second impedance to the voltage regulating circuit, and the bypass circuit is configured not to bypass the clamping component to provide a clamping voltage so that the feedback circuit is configured to notify the power supply device to step up the output voltage to a second voltage according to the first impedance and the clamping voltage.
11 . A method of controlling an Ethernet power source equipment, the Ethernet power source equipment configured to receive an input voltage and configured to couple to a load device; the Ethernet power source equipment comprising a power supply device and a control module, and the method comprising steps of: converting, by the power supply device, the input voltage into an output voltage, and providing the output voltage to the load device through an output terminal, disconnecting a power supplying path between the output terminal and the control module to disable the control module when the Ethernet power source equipment detects that the load device is not coupled to the power supply device, adjusting the output voltage to a first voltage according to the load device not being coupled to the power supply device, connecting the power supplying path to enable the control module when the Ethernet power source equipment detects that the load device is coupled to the power supply device, and adjusting the output voltage to a second voltage according to the load device being coupled to the power supply device.
12 . The method of controlling the Ethernet power source equipment as claimed in claim 11 , wherein the output terminal comprises a first end and a second end, and the method further comprises steps of: providing an impedance according to a potential of the first end, providing a first impedance according to the load device not being coupled to the power supply device and the potential of the first end is in a first potential, adjusting the output voltage to the first voltage according to the first impedance, providing a second impedance according to the load device being coupled to the power supply device, and adjusting the output voltage to the second voltage according to the second impedance.
13 . The method of controlling the Ethernet power source equipment as claimed in claim 12 , wherein the first impedance and the second impedance are provided by a first voltage dividing circuit and a second voltage dividing circuit, and the method further comprises steps of: not bypassing the second voltage dividing circuit according to the load device not being coupled to the power supply device and the potential of the first end is in the first potential so as to provide the first impedance formed by the first voltage dividing circuit and the second voltage dividing circuit, and bypassing the second voltage dividing circuit according to the load device being coupled to the power supply device so as to provide the second impedance formed by the first voltage dividing circuit.
14 . The method of controlling the Ethernet power source equipment as claimed in claim 13 , further comprising steps of: providing a first feedback signal according to the first impedance, adjusting, by the power supply device, the output voltage to the first voltage according to the first feedback signal, adjusting the feedback signal to a second feedback signal according to the second impedance, and adjusting, by the power supply device, the output voltage to the second voltage according to the second feedback signal.
15 . The method of controlling the Ethernet power source equipment as claimed in claim 12 , further comprising steps of: providing a clamping voltage according to the load device being coupled to the power supply device so that a voltage between the second end and a ground terminal is equal to the sum of a regulated voltage and the clamping voltage, and not providing the clamping voltage according to the load device not being coupled to the power supply device and the potential of the first end is in the first potential.
16 . The method of controlling the Ethernet power source equipment as claimed in claim 12 , further comprising steps of: providing the first impedance when the potential of the first end is in the first potential and the power supplying path is disconnected according to a first path voltage, and providing the second impedance when the potential of the first end is in a second potential and the power supplying path is short-circuited according to a second path voltage.

Description

BACKGROUND Technical Field The present disclosure relates to an Ethernet power source equipment, a control circuit, and a method of controlling the same, and more particularly to an Ethernet power source equipment with power saving function, a step-down control circuit, and a method of controlling the same. Description of Related Art The statements in this section merely provide background information related to the present disclosure and do not necessarily constitute prior art. Power over Ethernet (PoE) is a variety of standardized technologies or its own standard technologies that can transmit power and data to devices through twisted pairs in an Ethernet network. This technology mainly uses an Ethernet power source equipment (PSE) to couple to a powered device (PD) through at least one RJ45 network cable to simultaneously transmit power and data to the powered device. Therefore, this technology can be used without additional power sockets so that Ethernet PSE does not require additional power sockets, thereby saving the time and cost of configuring power wires. However, most of the products currently on the market rely on full-time signal communication between the Ethernet PSE and the powered device (PD) to determine whether the PSE should supply power to the correct PD. Therefore, even when the PD is not connected or the PD has been disconnected, the PSE will continue to send handshake signals for detection so that power will continue to be lost when the PSE is in standby, and therefore the current PSE cannot meet the current energy efficiency regulations (such as but not limited to DoE, EC CoC, and other energy regulations) for power consumption under no load conditions. Therefore, how to design an Ethernet PSE to reduce the power consumption of the Ethernet PSE as much as possible when the powered device is not connected to the Ethernet PSE has become a critical topic in this field. SUMMARY In order to solve the above-mentioned problems, the present disclosure provides an Ethernet power source equipment (PSE). The Ethernet PSE couples to a load device, and the Ethernet PSE includes a power supply device, an output control circuit, a path control circuit, and a control module. The power supply device converts an input voltage into an output voltage, and provides the output voltage to the load device through an output terminal. The output control circuit is coupled to the output terminal, and adjusts the output voltage to a first voltage or a second voltage based on whether the load device is coupled to the output terminal. The path control circuit is coupled to the output terminal. The control module is coupled to the path control circuit. When the output control circuit detects that the load device is not coupled to the output terminal, the path control circuit disconnects a power supplying path between the output terminal and the control module, and the output control circuit adjusts the output voltage to the first voltage so that the control module enters a disabled state. When the output control circuit detects that the load device is coupled to the output terminal, the path control circuit connects the power supplying path, and the output control circuit adjusts the output voltage to the second voltage so that the control module enters an enabled state. In order to solve the above-mentioned problems, the present disclosure provides a step-down control circuit. The step-down control circuit is applied to an Ethernet power source equipment (PSE), and the Ethernet PSE includes a power supply device for providing an output voltage through a first end and a second end. The power supply device includes a feedback control circuit, and the feedback control circuit includes a clamping component coupled to the second end of the power supply device in series, a feedback circuit, and a voltage regulating circuit, and a first voltage dividing circuit coupled to the second end and the voltage regulating circuit. The step-down control circuit includes a second voltage dividing circuit and an impedance control circuit. The second voltage dividing circuit is coupled to the first voltage dividing circuit in series. The impedance control circuit is coupled to the second voltage dividing circuit in parallel and coupled to the first end, and the impedance control circuit selectively bypasses the second voltage dividing circuit to provide a first impedance or a second impedance to the voltage regulating circuit. The bypass circuit is coupled to the first end and coupled to the clamping component in parallel. A power pin of a controller of the Ethernet PSE is coupled to the impedance control circuit and the bypass circuit; when a potential of the first end is in a first potential, and a power supplying path between the second end and the power pin is disconnected to provide a first path voltage to the impedance control circuit, the impedance control circuit does not bypass the second voltage dividing circuit to provide