Method for dynamic insertion loss control for 10/100/1000 MHz Ethernet signaling
First Claim
Patent Images
1. An insertion loss control limit circuit operable to supply an insertion loss limit to a coupled power feed circuit, the insertion loss control limit circuit comprising:
- a first amplifier operably coupled to a pair of network power signals, wherein the amplifier is operable to generate a power estimate signal associated with the network power signals;
a rectifier operable to convert the power estimate signal into a single ended rectified power estimate; and
a loop filter operable to produce an insertion loss control limit, wherein the insertion loss control limit is based on the received pair of network power signals.
3 Assignments
0 Petitions
Accused Products
Abstract
Dynamic insertion insertion loss for an ethernet power on differential cable pairs is shown in a power feed circuit that supplies power to a network attached device (PD). An insertion loss control circuit limits power loss in a coupled power feed circuit. determines an insertion loss limit, and senses an average power of the power signals to produce a common mode feedback signal to the power feed circuit.
-
Citations
21 Claims
-
1. An insertion loss control limit circuit operable to supply an insertion loss limit to a coupled power feed circuit, the insertion loss control limit circuit comprising:
-
a first amplifier operably coupled to a pair of network power signals, wherein the amplifier is operable to generate a power estimate signal associated with the network power signals; a rectifier operable to convert the power estimate signal into a single ended rectified power estimate; and a loop filter operable to produce an insertion loss control limit, wherein the insertion loss control limit is based on the received pair of network power signals. - View Dependent Claims (2, 3, 4)
-
-
5. A power feed circuit operable to supply power to an Ethernet network device coupled to an Ethernet network, comprising:
-
two differential transistor pairs wherein each transistor is operable to pass an Ethernet power signal; two pairs of impedance sense resistors coupled to a transistor, wherein each impedance sense resistors is operable to pass a Ethernet power signals received from a drain of the coupled transistor; an insertion loss control limit circuit operable to provide a insertion loss limit to a common mode feedback amplifier, wherein the common mode feedback amplifier senses an average Ethernet power signal and wherein the common mode feedback amplifier outputs a common mode feedback signal; a differential amplifier coupled to the drains of each differential transistor pair, wherein the differential amplifier(s) are operable to;
receive the common mode feedback signal;amplify a differential voltage across the pair of impedances coupled to the differential transistor pair; and apply a feedback signal to a gate of the transistors of each differential transistor pair based on the differential voltage and common mode feedback signal, wherein the applied feedback signal; drives the Ethernet power signal passed by each transistor in a differential transistor pair to be equal; and reduces the insertion loss to the insertion loss limit; and a pair of output nodes, wherein one output node is associated with each differential transistor pair, and wherein the pair of output nodes feed power to the Ethernet network device. - View Dependent Claims (6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
-
-
17. A method to at least partially power an Ethernet network powered device, from an Ethernet power signal fed through an Ethernet network connection, comprising:
-
receiving a plurality of paired Ethernet power signals; passing each pair of Ethernet power signal through a differential transistor pairs; sensing a drain voltage at a drain of each transistor; determining an insertion loss limit associated with the Ethernet power signals; determining a common mode feedback signal based on the Ethernet power signals and insertion loss limit;
comparing the drain voltages of each differential transistor producing a pair of control signals for each differential transistor pair based on;the comparison of the drain voltages of each differential transistor pair; and the common mode feedback signal; applying the control signal to a gate of each transistor, wherein the control signal; equalizes the Ethernet power signal passed by each transistor in a differential transistor pair; and limits the insertion loss associated with the Ethernet power signal; and passing the Ethernet power signal from a pair of output nodes wherein one output node is associated with each differential transistor pair, and wherein the pair of output nodes feed power to the Ethernet network device. - View Dependent Claims (18, 19, 20, 21)
-
Specification