Power source equipment and power supply control method
AssigneeRealtek Semiconductor Corp.
InventorChien Sheng Chen
Life of this patent
Estimating the term…
Abstract
A power source equipment is configured to provide a power to a powered device in a power over Ethernet. The power source equipment includes a first port, a second port, and a control circuit. The first port is configured to perform a power classification on the powered device, and provide a first voltage to the powered device in a first stage. The second port is configured to provide a second voltage to the powered device in a second stage. The control circuit is configured to disable the second port in the first stage, and configured to control the second port to output the second voltage and increase the first voltage in the second stage.
Claims19
A power source equipment (PSE) configured to provide a power to a powered device (PD) in a power over Ethernet system (PoE), the power source equipment comprising:
- a first port configured to perform a power classification on the PD and output a first cross voltage to the PD in a first stage;
- a second port configured to output a second cross voltage to the PD in a second stage;
- and
- a control circuit configured to disable the second port in the first stage, and control the second port to output the second cross voltage and increase the first cross voltage in the second stage,
- wherein the control circuit comprises:
- a first transistor;
- a second transistor;
- and
- an amplifier,
- wherein
- a first terminal of the first transistor is configured to receive a first voltage from the PD through the first port, and a first terminal of the second transistor is configured to receive a second voltage from the PD through the second port,
- a control terminal of the first transistor and a control terminal of the second transistor are coupled to an output terminal of the amplifier,
- a second terminal of the first transistor and a second terminal of the second transistor are coupled to a second supply voltage, and
- a positive receiving terminal of the amplifier is coupled to the first terminal of the first transistor, and a negative receiving terminal is coupled to a first reference voltage or a second reference voltage.
A power supply control method configured to control a power source equipment (PSE) to supply a power to a powered device (PD) in a power over Ethernet system (PoE), the power supply control method comprising:
- in a first stage of the power supply control method, performing a power classification on the PD, and controlling a first port of the PSE to output a first cross voltage to the PD, comprising:
- receiving, by a first terminal of a first transistor, a first voltage from the PD through a first negative terminal of the first port;
- disabling a second port of the PSE in the first stage;
- controlling the second port to output a second cross voltage to the PD in a second stage of the power supply control method, comprising:
- receiving, by a first terminal of a second transistor, a second voltage from the PD through a second negative terminal of the second port;
- and
- increasing the first cross voltage in the second stage, comprising:
- decreasing the first voltage, comprising:
- receiving a reference voltage by a negative receiving terminal of an amplifier;
- and
- outputting a control voltage by the amplifier to a control terminal of the first transistor and a control terminal of the second transistor,
- wherein a second terminal of the first transistor and a second terminal of the second transistor are coupled to a second supply voltage, a positive receiving terminal of the amplifier is coupled to the first terminal of the first transistor, and a negative receiving terminal is coupled to the reference voltage.
Dependencies are inferred from the claim text.