D-link Corporation

Alpha Networks Inc.

Pao-Ching Hu

Wei-Hung Tsai

Chung-Wang Lee

Tien-Hsiung Tung

Mei-Chuan Chen

Mei-Yi Chen

Hsiu-Chu Tsao

Huai-Tung Lee

Fang Yu

The present invention provides a relay-based foolproof circuit for over-voltage protection, which is electrically connected between a plug and an electric device, and includes a relay having at least one magnetic core, a coil wound around the magnetic core and two reed switches each having a reed and being normally in a closed state because of the elastic effect of its reed. The relay-based foolproof circuit is able to provide AC power of a first specification (e.g., 110 V AC power) received from the plug to the electric device. However, when AC power of a second specification (e.g., 220 V AC power) greater than the first specification flows through the coil, the coil causes the magnetic core to generate a magnetic force great enough to drive the two reed switches into an open state for stopping the AC power of the second specification from being provided to the electric device.

Relay-based foolproof circuit for over-voltage protection

A dual speed hub includes a CPU, two hubs of different transmission speeds, two MACs (media access controls), and a switch, wherein the CPU periodically sends a test packet in proper order through one MAC, one hub, the switch and the other hub to the other MAC, then checks the receiving condition and the content of the returned test packet, then determines the normality of the function of the switch subject to the receiving condition and the content of the returned test packet, and then provides a warning signal to a network management system when the switch is judged abnormal, informing the network manager to repair the switch.

Dual speed hub, and the related redundant switching method

Growing community of inventors

Hsinchu, Taiwan

Pao-Ching Hu