Power over ethernet powered device interface with non-power over ethernet supply detection

Patent metadata

Field	Value
Publication number	US-9665151-B1
Application number	US-201314036242-A
Country	US
Kind code	B1
Filing date	Sep 25, 2013
Priority date	Sep 27, 2012
Publication date	May 30, 2017
Grant date	May 30, 2017

Abstract

A method for detecting and classifying powered devices in power over Ethernet/non-power over Ethernet applications is described. In one or more implementations, the method includes deactivating a non-power over Ethernet component for a predetermined time period. The method also includes activating an isolation switch of a powered device after the predetermined time period has elapsed since no characteristic impedance associated with the powered device has been detected.

First claim

What is claimed is:

1. A system, comprising:
a powered device having an integrated powered device controller, the powered device comprising an interface configured to electrically couple to a power over Ethernet component and a non-power over Ethernet component, the powered device including
a non-power over Ethernet voltage detection circuit configured to support low input voltage over the interface;
a time delay circuit configured to provide a delay time for the non-power over Ethernet voltage detection circuit to detect voltage to the powered device over the interface; and
an isolation switch operatively coupled to the time delay circuit, the time delay circuit configured to cause the isolation switch to transition to an on configuration after the delay time has elapsed when no characteristic impedance associated with the powered device has been detected over the interface,
wherein the time delay circuit is configured to allow power over Ethernet to start up with higher priority during the predetermined time period when the integrated powered device controller detects a characteristic impedance corresponding to the powered device over the interface and the integrated powered device controller classifies the powered device based upon a current draw corresponding to the powered device when the characteristic impedance is detected.

2. The system of claim 1 , wherein the integrated powered device controller has up to 900 ms to power up after voltage detection by the non-power over Ethernet voltage detection circuit starts.

3. The system of claim 1 , wherein the integrated powered device controller exhibits high impedance so that an approximately 25.5 kohm signature is correctly detected by power sourcing equipment.

4. The system of claim 1 , wherein the non-power over Ethernet voltage detection circuit is configured to detect a voltage lower than 10 volts.

5. The system of claim 1 , wherein the non-power over Ethernet voltage detection circuit is configured to detect current less than 10 μA.

6. A method, comprising:
detecting a non-power over Ethernet voltage using a non-power over Ethernet voltage detection circuit in an integrated powered device controller, the powered device comprising an interface an interface configured to electrically couple to a power over Ethernet component and a non-power over Ethernet component, the non-power over Ethernet voltage supplied to a powered device over the interface; and
activating an isolation switch of the powered device using a time delay circuit after a predetermined time period has elapsed when no characteristic impedance associated with the powered device has been detected over the interface, wherein the non-power over Ethernet component exhibits a characteristic impedance configured not to interfere with the powered device detection and classification signature,
wherein the time delay circuit is configured to allow power over Ethernet to start up with higher priority during the predetermined time period when the integrated powered device controller detects a characteristic impedance corresponding to the powered device over the interface and the integrated powered device controller classifies the powered device based upon a current draw corresponding to the powered device when the characteristic impedance is detected.

7. The method of claim 6 , wherein the integrated powered device controller has up to 900 ms to power up after voltage detection by the non-power over Ethernet voltage detection circuit starts.

8. The method of claim 6 , wherein the integrated powered device controller exhibits high impedance so that an approximately 25.5 kohm signature is correctly detected by power sourcing equipment.

9. The method of claim 6 , wherein the non-power over Ethernet voltage detection circuit is configured to detect a voltage lower than 10 volts.

10. The method of claim 6 , wherein the non-power over Ethernet voltage detection circuit is configured to detect current less than 10 μA.

11. A method, comprising:
deactivating a non-power over Ethernet component for a predetermined time period using an integrated powered device controller having a non-power over Ethernet voltage detection circuit, the non-power over Ethernet component connected in a power over Ethernet network environment, the integrated powered device controller disposed within a powered device, the powered device comprising an interface electrically connected to the non-power over Ethernet component and a power over Ethernet component; and
activating an isolation switch of a powered device using a time delay circuit in the integrated powered device controller after the predetermined time period has elapsed when no characteristic impedance associated with the powered device has been detected over the interface, wherein the non-power over Ethernet component exhibits a characteristic impedance configured not to interfere with the powered device detection and classification signature,
wherein the time delay circuit is configured to allow power over Ethernet to start up with higher priority during the predetermined time period when the integrated powered device controller detects a characteristic impedance corresponding to the powered device over the interface and the integrated powered device controller classifies the powered device based upon a current draw corresponding to the powered device when the characteristic impedance is detected.

12. The method of claim 11 , wherein the integrated powered device controller has up to 900 ms to power up after voltage detection by the non-power over Ethernet voltage detection circuit starts.

13. The method of claim 11 , wherein the integrated powered device controller exhibits high impedance so that an approximately 25.5 kohm signature is correctly detected by power sourcing equipment.

14. The method of claim 11 , wherein the non-power over Ethernet voltage detection circuit is configured to detect a voltage lower than 10 volts.

15. The method of claim 11 , wherein the non-power over Ethernet voltage detection circuit is configured to detect current less than 10 μA.

Assignees

• Maxim Integrated Products

Inventors

• Zou Gaoling
• Huynh Thong A
• Ranzato Mauro
• Vigna Andrea
• Mariano Gianluca

Classifications

• G06F1/28 Primary

  Supervision thereof, e.g. detecting power-supply failure by out of limits supervision · CPC title

• G06F1/26

  Power supply means, e.g. regulation thereof (for memories G11C) · CPC title

• G06F1/266

  Arrangements to supply power to external peripherals either directly from the computer or under computer control, e.g. supply of power through the communication port, computer controlled power-strips · CPC title