Bus system i.e. Joint test action group chain, for e.g. testing digital and/or analog integrated circuits by boundary scan test, has switch input interconnected to output based on magnitude of control voltage applied at voltage terminal

摘要

The system has a switch (30) i.e. multiplexer, including an output (36), which is connected with a data signal line-output terminal (28). An input (32) of the switch is connected with a data signal line-input terminal (26). A hardware component-input terminal (40) is connected with another input (34) of the switch. Terminal units (14, 16,) include a control voltage terminal (50), which is connected with a control terminal (38) of the switch. One of the inputs of the switch is interconnected to the output of the switch based on a magnitude of a control voltage applied at the voltage terminal.