Apparatus and method for non-latching, bi-directional communication over an electrically isolated data link

摘要

An isolation apparatus and method are provided for bi-directional communication over a single wire link without circuit latch up. The isolation is provided by two identical but independent switching circuits designed to eliminate latch up while controlling two optical isolators in a bi-directional mode of operation.

主权项

1. An isolation circuit, comprising:
first and second split data lines for bi-directional operation, wherein both the split data lines are coupled to open drain or open collector devices for preventing latch up by operating one of the open drain or open collector devices to switch a cathode of an optocoupler LED from a logic high to a logic low while simultaneously operating the other open drain or open collector device to switch an anode of the optocoupler LED from a logic high to a logic low, thereby maintaining the optocoupler LED off.