Patent ID: 8525547

Claim:
An isolator device, comprising a plurality of isolation devices bridging an isolation barrier between an upstream circuit sub-system and a downstream circuit sub-system, each of the upstream circuit sub-system and the downstream circuit sub-system comprising: a USB transceiver for exchanging USB signals with respective external components, and an isolator transceiver coupled to the respective USB transceiver to exchange signals between the USB transceiver and the isolation devices; wherein, for at least one circuit sub-system, the isolator transceiver transmitter includes a pulse generator and a refresh pulse generator to generate pulses in response to an input logic signal and to repeat the generated pulses according to a refresh interval, and wherein, for at least the other circuit sub-system, the isolator transceiver receiver includes a watchdog timer to maintain the receiver in a reception state if pulses are received within a watchdog interval.