Abstract: An integrated circuit (100) has a plurality of inputs (110) and a plurality of outputs (120). In a test mode, a test arrangement including a plurality of logic gates (140) is coupled between the plurality of inputs (110) and the plurality of outputs (120). The logic gates from the plurality of logic gates (140) have a first input coupled to an input of the plurality of inputs (110) and a further input coupled to a fixed logic value source (150). The fixed logic value source (150) is used to define an identification code of the integrated circuit (100), which can be retrieved at the plurality of outputs (120) when an appropriate bit pattern is fed to the plurality of inputs (110).

Abstract: An integrated circuit with a test interface contains a boundary scan chain with cells (14) coupled between a test data input (TDI) and output (TDO) in a shift register structure. Each cell (14) is also coupled between a respective one of the terminals (16) and the core circuit (10). A test control circuit (TAP_C) supports an instruction to switch the boundary scan chain to a mode in which mode selectable first ones of the cells (14) transport data serially along the boundary scan chain while selectable second ones of the cells (14) write or read data that has been or will be transported through the first ones of the cells (14) in the further mode to or from the terminals (16) from or to the scan chain.

Abstract: A test arrangement for testing the interconnections of an electronic circuit (100) and a further electronic circuit is provided. A first selection of I/O nodes (120), which are arranged to receive input data in a functional mode of the electronic circuit (100), and which are coupled to a test unit in a test mode of the electronic circuit (100). The test unit has a combinatorial circuit (160) for implementing a multiple-input XOR or XNOR gate. The test unit also provides interconnections between the first selection of I/O nodes (120) and a second selection of I/O nodes (130) via logic gates (141–144). These interconnections increase the interconnect test coverage of the electronic device (100), because the interconnects with the further electronic circuits that are associated with I/O nodes (131–134) become testable as well.