Patent ID: 8076793
Filing Date: 2011-12-13
Classification: H04L

Abstract:
1. In a Power over Ethernet system, an isolation circuit for providing electrical isolation of Power Sourcing Equipment (PSE) circuitry from external circuitry, the isolation circuit comprising: a first inductive circuit for providing an isolation barrier to electrically isolate an isolated side of the isolation circuit from a non-isolated side of the isolation circuit, a first node configured at the non-isolated side for providing connection to the external circuitry, a second node configured at the isolated side for providing connection to the PSE circuitry, and signal path circuitry configured for transferring a first signal in a first direction from the first node to the second node, and in a second direction from the second node to the first node; the signal path circuitry including: a first transfer circuit and a second transfer circuit, the first transfer circuit being configured for transmitting the first signal in the first direction to the second transfer circuit over the isolation barrier, the second transfer circuit being configured for transmitting the first signal in the second direction to the first transfer circuit over the isolation barrier; a first arbitration circuit having a first input responsive to the first signal transferred from the first node in the first direction, a second input responsive to the first signal transferred in the second direction, a first output for transferring the first signal to the first transfer circuit in the first direction, and a control output, and a first gate circuit controlled by the control output of the first arbitration circuit and having an output for transferring the first signal to the first node in the second direction.